Association of Adverse Childhood Experiences and Resilience With Depression and Anxiety During Pregnancy
This was a retrospective cohort study of pregnant individuals in the Kaiser Permanente Northern California system who were screened for adverse childhood experiences and resilience as part of standard prenatal care at about 16 weeks of gestation. Overall, 14,625 pregnancies…
Long-Term Risk of Reintervention After Surgical Leiomyoma Treatment in an Integrated Health Care System
To compare long-term risk of reintervention across four uterus-preserving surgical treatments for leiomyomas and to assess effect modification by sociodemographic factors in a prospective cohort study in an integrated health care delivery system. We studied a cohort of 10,324 patients…
Using Electronic Health Records to Improve HIV Preexposure Prophylaxis Care: A Randomized Trial
Preexposure prophylaxis (PrEP) use remains limited and inequitable, and strategies are needed to improve PrEP provision in primary care. We conducted a cluster randomized trial at Kaiser Permanente, San Francisco, to evaluate the effectiveness of a clinical decision support intervention…
Longitudinal Changes in Sex Hormone Binding Globulin (SHBG) and Risk of Incident Diabetes: The Study of Women’s Health Across the Nation (SWAN)
To investigate the associations of longitudinal changes in sex hormone binding globulin (SHBG) and testosterone (T) over the menopause transition with the risk of diabetes. We followed 2,952 participants in the Study of Women's Health Across the Nation (SWAN) who…
Interim Effectiveness of Updated 2023-2024 (Monovalent XBB.1.5) COVID-19 Vaccines Against COVID-19-Associated Hospitalization Among Adults Aged ≥18 Years with Immunocompromising Conditions – VISION Network, September 2023-February 2024
In September 2023, CDC's Advisory Committee on Immunization Practices recommended updated 2023-2024 (monovalent XBB.1.5) COVID-19 vaccination for all persons aged ≥6 months to prevent COVID-19, including severe disease. As with past COVID-19 vaccines, additional doses may be considered for persons…
Effectiveness of an Artificial Intelligence-Enabled Intervention for Detecting Clinical Deterioration
Inpatient clinical deterioration is associated with substantial morbidity and mortality but may be easily missed by clinicians. Early warning scores have been developed to alert clinicians to patients at high risk of clinical deterioration, but there is limited evidence for…
Vaccine Effectiveness Against Pediatric Influenza-A-Associated Urgent Care, Emergency Department, and Hospital Encounters During the 2022-2023 Season, VISION Network
During the 2022-2023 influenza season, the United States experienced the highest influenza-associated pediatric hospitalization rate since 2010-2011. Influenza A/H3N2 infections were predominant. We analyzed acute respiratory illness (ARI)-associated emergency department or urgent care (ED/UC) encounters or hospitalizations at 3 health…
Initial antiretroviral therapy regimen and risk of heart failure
Heart failure risk is elevated in people with HIV (PWH). We investigated whether initial antiretroviral therapy (ART) regimens influenced heart failure risk. Cohort study. PWH who initiated an ART regimen between 2000 and 2016 were identified from three integrated healthcare…
Mortality risk after COVID-19 vaccination: A self-controlled case series study
Although previous studies found no-increased mortality risk after COVID-19 vaccination, residual confounding bias might have impacted the findings. Using a modified self-controlled case series (SCCS) design, we assessed the risk of non-COVID-19 mortality, all-cause mortality, and four cardiac-related death outcomes…
On- and Off-Label Atypical Antipsychotic Prescription Trends Across a Nine-Year Period Among Adolescents Pre- to Post-COVID-19
This study examined atypical antipsychotic prescribing by Food and Drug Administration (FDA) approved-use (on-label) status for adolescents before and during the COVID-19 pandemic. Retrospective data were collected from electronic health records (EHRs) of adolescents aged 10-17 years in Kaiser Permanente…
Alanine aminotransferase elevation varies by ethnicity among Asian and Pacific Islander children with overweight or obesity
Limited research on alanine aminotransferase (ALT) screening for metabolic dysfunction-associated steatotic liver disease (MASLD) among US Asian/Pacific Islander (PI) children necessitates investigation in this heterogeneous population. Examine ALT elevation among Asian/PI children with overweight or obesity. Elevated ALT prevalence (clinical…
Challenges of fracture risk assessment in Asian and Black women
Bone mineral density (BMD) and fracture risk calculators (eg, the Fracture Risk Assessment Tool [FRAX]) guide primary prevention care in postmenopausal women. BMD scores use non-Hispanic White (NHW) reference data for T-score classification, whereas FRAX incorporates BMD, clinical risk factors,…
Behavior reallocations within 24-h movement profiles and change in cardiometabolic biomarkers during pregnancy
The goal of this study was to investigate associations of reallocations within 24-h movement profiles and changes in cardiometabolic biomarkers from early to late pregnancy. In 137 individuals with prepregnancy overweight/obesity, waking movement was measured using wrist-worn accelerometers, sleep was…
Interim Effectiveness of Updated 2023-2024 (Monovalent XBB.1.5) COVID-19 Vaccines Against COVID-19-Associated Emergency Department and Urgent Care Encounters and Hospitalization Among Immunocompetent Adults Aged ≥18 Years – VISION and IVY Networks, September 2023-January 2024
In September 2023, CDC's Advisory Committee on Immunization Practices recommended updated 2023-2024 (monovalent XBB.1.5) COVID-19 vaccination for all persons aged ≥6 months to prevent COVID-19, including severe disease. However, few estimates of updated vaccine effectiveness (VE) against medically attended illness…
Differences in Smoking Behavior by Nativity, Race/Ethnicity, and Education Among Women Diagnosed with Breast Cancer
We evaluated smoking differences across nativity and race/ethnicity among women diagnosed with breast cancer. In our Northern Californian pooled population of 5,653 [670 Asian, 690 Hispanic, and 4,300 Non-Hispanic White (White)] women diagnosed with breast cancer, we evaluated smoking differences…
Changes in Body Mass Index Over Time in People With and Without HIV Infection
Excess weight gain is an important health concern among people with HIV (PWH) on antiretroviral therapy (ART). The extent to which ART contributes to body mass index (BMI) changes is incompletely understood. We conducted a retrospective study of PWH initiating…
Effectiveness of Recombinant Zoster Vaccine Against Herpes Zoster in a Real-World Setting
A 2-dose series of recombinant zoster vaccine (RZV) was 97% effective against herpes zoster (HZ) in a pivotal clinical trial. To evaluate real-world effectiveness of RZV against HZ. Prospective cohort study. Four health care systems in the Vaccine Safety Datalink.…
Telehealth Collaborative Care Led by Clinical Pharmacists for People With Psychosis or Bipolar Disorder: A Propensity Weighted Comparison With Usual Psychiatric Care
Objective: People with psychosis or bipolar disorder (severe and persistent mental illness [SPMI]) are at high risk for poor psychiatric and chronic illness outcomes, which could be ameliorated through improved health care quality. This study assessed whether a telehealth, collaborative…
Effect of home-based resistance training on chemotherapy relative dose intensity and tolerability in colon cancer: The FORCE randomized control trial
Many patients with colon cancer cannot fully adhere to postoperative chemotherapy due to dose-limiting toxicities, resulting in lower relative dose intensity (RDI) and potentially compromising overall survival. This study examined whether home-based resistance training (RT) during adjuvant chemotherapy improves RDI and patient-reported…
A polygenic score associated with fracture risk in breast cancer patients treated with aromatase inhibitors
Identifying women at high risk of osteoporotic fracture from aromatase inhibitor (AI) therapy for breast cancer is largely based on known risk factors for healthy postmenopausal women, which might not accurately reflect the risk in breast cancer patients post-AI therapy.…
Advances in Adherence Reporting of Resistance Training in a Clinical Trial during Adjuvant Chemotherapy for Colon Cancer
Detailed reporting of individually tailored exercise prescriptions (ExRx) used in clinical trials is essential to describe feasibility, tolerability, and efficacy of the intervention and to inform translation to clinical care. This paper outlines the methodology used to develop a resistance…
Cardiovascular Disease Risk Factor Control in People With and Without Human Immunodeficiency Virus
Management of hypertension, dyslipidemia, diabetes and other modifiable factors may mitigate the cardiovascular disease (CVD) risk in people with human immunodeficiency virus (HIV, PWH) compared with people without HIV (PWoH). This was a retrospective cohort study of 8285 PWH and…
Community-Wide Universal Human Immunodeficiency Virus (HIV) Test and Treat Intervention Reduces Tuberculosis Transmission in Rural Uganda: A Cluster-Randomized Trial
Human immunodeficiency virus (HIV) treatment reduces tuberculosis (TB) disease and mortality; however, the population-level impact of universal HIV-test-and-treat interventions on TB infection and transmission remain unclear. In a sub-study nested in the SEARCH trial, a community cluster-randomized trial (NCT01864603), we…
Reproductive Health Care in Adolescents with Autism and Other Developmental Disabilities
Adults with developmental disabilities often have less access to reproductive health services than adults without these disabilities. However, little is known about how adolescents with developmental disabilities, including autism, access reproductive health care. We aimed to characterize the utilization of…
Evaluation of an outreach programme for patients with COVID-19 in an integrated healthcare delivery system: a retrospective cohort study
In the first year of the COVID-19 pandemic, health systems implemented programmes to manage outpatients with COVID-19. The goal was to expedite patients' referral to acute care and prevent overcrowding of medical centres. We sought to evaluate the impact of…
Randomized trial of patient outreach approaches to de-implement outdated colonoscopy surveillance intervals
Guidelines now recommend patients with low-risk adenomas receive colonoscopy surveillance in 7-10 years and those with the previously recommended 5-year interval be reevaluated. We tested three outreach approaches for transitioning patients to the 10-year interval recommendation. Design: 3-arm pragmatic randomized…
Inflammatory Conditions During Pregnancy and Risk of Autism and Other Neurodevelopmental Disorders
Maternal inflammation can result from immune dysregulation and metabolic perturbations during pregnancy. Whether conditions associated with inflammation during pregnancy increase the likelihood of autism spectrum disorder (ASD) or other neurodevelopmental disorders (DDs) is not well understood. We conducted a case-control…
Evaluation of the international Ki67 working group cut point recommendations for early breast cancer: comparison with 21-gene assay results in a large integrated health care system
The International Ki67 Working Group (IKWG) has developed training for immunohistochemistry (IHC) scoring reproducibility and recommends cut points of ≤ 5% and ≥ 30% for prognosis in ER+, HER2-, stage I/II breast cancer. We examined scoring reproducibility following IKWG training and evaluated these cut…
Agreement Between Self-reports and Urine Toxicology Measures of Illicit Methamphetamine and Cocaine Use During Early Pregnancy
This study aimed to assess agreement between self-report and urine toxicology measures assessing use of 2 illicit simulants (methamphetamine and cocaine) during early pregnancy. This cross-sectional study of 203,053 pregnancies from 169,709 individuals receiving prenatal care at Kaiser Permanente Northern…
Timing and level of educational attainment and late-life cognition in the KHANDLE study
The timing of educational attainment may modify its effects on late-life cognition, yet most studies evaluate education only at a single time point. Kaiser Healthy Aging and Diverse Life Experiences (KHANDLE) Study cohort participants (N = 554) reported educational attainment (dichotomized at…
Clinical outcomes in hospitalized plasma and platelet transfusion recipients prior to and following widespread blood donor SARS-CoV-2 infection and vaccination
The safety of transfusion of SARS-CoV-2 antibodies in high plasma volume blood components to recipients without COVID-19 is not established. We assessed whether transfusion of plasma or platelet products during periods of increasing prevalence of blood donor SARS-CoV-2 infection and…
Recombinant or Standard-Dose Influenza Vaccine in Adults under 65 Years of Age
Quadrivalent recombinant influenza vaccines contain three times the amount of hemagglutinin protein as standard-dose egg-based vaccines, and the recombinant formulation is not susceptible to antigenic drift during manufacturing. Data are needed on the relative effectiveness of recombinant vaccines as compared…
Environmental and Occupational Exposures and Prognosis in Patients with Non-Muscle Invasive Bladder Cancer in the Be-Well Study
Bladder cancer is primarily diagnosed as non-muscle invasive bladder cancer (NMIBC) with high recurrence and progression rates. Environmental and occupational exposures to carcinogens are well-known risk factors for developing bladder cancer, yet their effects on prognosis remain unknown. In the…
Influenza vaccine effectiveness against influenza-A-associated emergency department, urgent care, and hospitalization encounters among U.S. adults, 2022-2023
The 2022-2023 United States influenza season had unusually early influenza activity with high hospitalization rates. Vaccine-matched A(H3N2) viruses predominated, with lower levels of A(H1N1)pdm09 activity also observed. Using the test-negative design, we evaluated influenza vaccine effectiveness (VE) during the 2022-2023…
Fracture Risk and Association With TDF Use Among People With HIV in Large Integrated Health Systems
Greater decline in bone health among people with HIV (PWH) has been documented but fracture risk and the impact of specific antiretroviral therapy (ART) regimens remain unclear. Retrospective analyses of electronic health record data from 3 US integrated health care…
Postpartum defects in inflammatory response after gestational diabetes precede progression to type 2 diabetes: a nested case-control study within the SWIFT study
Gestational diabetes (GDM) is a distinctive form of diabetes that first presents in pregnancy. While most women return to normoglycemia after delivery, they are nearly ten times more likely to develop type 2 diabetes than women with uncomplicated pregnancies. Current…
Intrinsic motivation for physical activity, healthy eating, and self-weighing in association with corresponding behaviors in early pregnancy
Healthy lifestyle behaviors influence maternal cardiovascular health, but motivation for them in pregnancy is poorly understood. We examined whether intrinsic motivation (assessed on 5-point scales for each behavior) is associated with three lifestyle behaviors in early pregnancy: physical activity, by…
Neonatal Outcomes Associated with In Utero Cannabis Exposure: A Population-Based Retrospective Cohort Study
The full spectrum of associations between in utero cannabis exposure and adverse neonatal outcomes is still unclear. This study evaluates associations between in utero cannabis exposure and neonatal outcomes. This population-based retrospective cohort study of singleton births among Kaiser Permanente…
Effectiveness of the live zoster vaccine during the 10 years following vaccination: real world cohort study using electronic health records
To assess the effectiveness of live zoster vaccine during more than 10 years after vaccination; and to describe methods for ascertaining vaccine effectiveness in the context of waning. Real world cohort study using electronic health records. Kaiser Permanente Northern California,…
Effectiveness of COVID-19 vaccination during pregnancy by circulating viral variant
SARS-CoV-2 infection in pregnancy can result in a spectrum of asymptomatic to critical COVID-19 outcomes, including hospitalization, admission to the intensive care unit, or death. This study aimed to investigate the effectiveness of messenger RNA COVID-19 vaccination during pregnancy against…
Neighborhood Disadvantage, Race and Ethnicity, and Postpartum Depression
Postpartum depression (PPD) is a debilitating condition with higher rates among Black individuals. Increasingly, neighborhood disadvantage is being recognized as a contributor to poor health and may be associated with adverse postpartum mental health; however, associations between neighborhood disadvantage, race…
Patient-reported Primary Care Video and Telephone Telemedicine Preference Shifts During the COVID-19 Pandemic
Patient perceptions of primary care telephone and video telemedicine and whether COVID-19 pandemic-related telemedicine exposure shifted patients' visit preference is unknown. We examined patient surveys to understand the health care experience of patients seeking primary care through telemedicine and how…
Independent Impact of Eat, Sleep, Console Assessment on Neonatal Opioid Withdrawal Syndrome
Compared with the Finnegan Neonatal Abstinence Scoring System (FNASS), the Eat, Sleep, Console (ESC) approach reduces pharmacotherapy and length of stay (LOS) for neonatal opioid withdrawal syndrome (NOWS) infants. The independent outcome contribution of ESC is unknown as the approach…
Impact of a scalable training program on the quality of colonoscopy performance and risk of post-colonoscopy colorectal cancer
Endoscopist adenoma detection rates (ADRs) vary widely and are associated with patients' risk of postcolonoscopy colorectal cancers (PCCRCs). However, few scalable physician-directed interventions demonstrably both improve ADR and reduce PCCRC risk. Among patients undergoing colonoscopy, we evaluated the influence of…
Association between maternal prenatal cannabis use and missed child preventive care visits in an integrated health care delivery system in Northern California
The periodicity of well-child visits recommended by the American Academy of Pediatrics emphasizes the importance of continuity of care in health management. Exposure to cannabis in utero has been associated with adverse development, and adherence to well-child visits is critical…
PFAS concentrations in early and mid-pregnancy and risk of gestational diabetes mellitus in a nested case-control study within the ethnically and racially diverse PETALS cohort
Per- and polyfluoroalkyl substances (PFAS) are persistent synthetic chemicals and are commonly found in everyday items. PFAS have been linked to disrupting glucose homeostasis, however, whether they are associated with gestational diabetes mellitus (GDM) risk remains inconclusive. We examined prospective…
Rabbani, Juleon
Challenges and Opportunities of Epidemiological Studies to Reduce the Burden of Cancers in Young Adults
There are >1.9 million survivors of adolescent and young adult cancers (AYA, diagnosed at ages 15-39) living in the U.S. today. Epidemiologic studies to address the cancer burden in this group have been a relatively recent focus of the research…
Individual and neighborhood factors associated with being unvaccinated against COVID-19 among pregnant persons
We investigated whether unvaccinated pregnant persons cluster geographically and determined factors associated with being unvaccinated using spatial and multivariate logistic regression analyses. Pregnant persons with deliveries from December 15, 2020, through September 30, 2022, at Kaiser Permanente Northern California were…
A demonstration of Modified Treatment Policies to evaluate shifts in mobility and COVID-19 case rates in U.S. counties
Mixed evidence exists of associations between mobility data and coronavirus disease 2019 (COVID-19) case rates. We aimed to evaluate the county-level impact of reducing mobility on new COVID-19 cases in summer/fall of 2020 in the United States and to demonstrate…
Blood donor, component, and recipient-specific factors associated with venous thromboembolism in transfused hospitalized adult patients: Data from the recipient epidemiology and donor evaluation Study-III (REDS-III)
Growing evidence suggests multiple pathophysiological mechanisms linking red blood cells (RBC) transfusions to thrombosis. This study examined blood donor, component, and recipient factors which may be associated with thromboembolic outcomes following RBC transfusion. We utilized the Recipient Epidemiology Donor Evaluation…
Protection of 2 and 3 mRNA Vaccine Doses Against Severe Outcomes Among Adults Hospitalized with COVID-19 – VISION Network, August 2021 – March 2022
We assessed coronavirus disease 2019 (COVID-19) vaccination impact on illness severity among adults hospitalized with COVID-19, August 2021-March 2022. We evaluated differences in intensive care unit (ICU) admission, in-hospital death, and length of stay among vaccinated (2 or 3 mRNA…
The prospective association of hyperandrogenism, oligomenorrhea and polycystic ovary syndrome with incident gestational diabetes: The coronary artery risk development in young adults women’s study
In this 28-year prospective study of 455 women (mean age: 26 years), polycystic ovary syndrome (PCOS) was associated with a 2.6-fold elevated risk of gestational diabetes (GDM). However, hyperandrogenism or oligomenorrhea in the absence of PCOS was not associated with GDM.
State-Level Indicators of Childhood Educational Quality and Incident Dementia in Older Black and White Adults
Higher educational attainment is associated with reduced dementia risk, but the role of educational quality is understudied, presenting a major evidence gap, especially as it may contribute to racial inequities. To evaluate the association between state-level educational quality during childhood…
Racial-Ethnic Differences in Treatment Initiation for New Diagnoses of Perinatal Depression
The adverse consequences of untreated perinatal depression highlight the need to identify populations to target in order to increase treatment rates. The authors sought to evaluate treatment initiation for a new diagnosis of depression during pregnancy or postpartum and to…
Development of cardiometabolic risk factors following endocrine therapy in women with breast cancer
Studies comparing the effect of aromatase inhibitor (AI) and tamoxifen use on cardiovascular disease (CVD) risk factors in hormone-receptor positive breast cancer (BC) survivors report conflicting results. We examined associations of endocrine therapy use with incident diabetes, dyslipidemia, and hypertension.…
Early Estimates of Bivalent mRNA Vaccine Effectiveness in Preventing COVID-19-Associated Emergency Department or Urgent Care Encounters and Hospitalizations Among Immunocompetent Adults – VISION Network, Nine States, September-November 2022
During June-October 2022, the SARS-CoV-2 Omicron BA.5 sublineage accounted for most of the sequenced viral genomes in the United States, with further Omicron sublineage diversification through November 2022.* Bivalent mRNA vaccines contain an ancestral SARS-CoV-2 strain component plus an updated…
TRENDS IN SMOKING-SPECIFIC LUNG CANCER INCIDENCE RATES WITHIN A U.S. INTEGRATED HEALTH SYSTEM, 2007-2018
At least 10% of lung cancers arise in adults who have never smoked. Data remain inconclusive on whether lung cancer incidence has been increasing among never-smoking adults. How have age-adjusted incidence rates of lung cancer changed temporally, especially among never-smoking…
Rates of malignancies among patients with moderate to severe atopic dermatitis: a retrospective cohort study
Patients with atopic dermatitis (AD), also known as eczema, may be at an increased risk for malignancies compared with patients without AD; however, incidence rates (IRs) of malignancies in patients with moderate to severe AD are largely unknown. The objective…
Associations between antidepressant use patterns during pregnancy and birth outcomes among periconception antidepressant users
Little is known about antidepressant medication use patterns during pregnancy among periconception (before and immediately following conception) users. Additionally, the associations between these patterns and birth outcomes is unclear, after taking into account underlying depression severity. This study describes patterns…
Human Immunodeficiency Virus Status, Tenofovir Exposure, and the Risk of Poor Coronavirus Disease 19 (COVID-19) Outcomes: Real-World Analysis From 6 United States Cohorts Before Vaccine Rollout
People with human immunodeficiency virus (HIV) (PWH) may be at increased risk for severe coronavirus disease 2019 (COVID-19) outcomes. We examined HIV status and COVID-19 severity, and whether tenofovir, used by PWH for HIV treatment and people without HIV (PWoH)…
Estimation of COVID-19 mRNA Vaccine Effectiveness and COVID-19 Illness and Severity by Vaccination Status During Omicron BA.4 and BA.5 Sublineage Periods
Recent SARS-CoV-2 Omicron variant sublineages, including BA.4 and BA.5, may be associated with greater immune evasion and less protection against COVID-19 after vaccination. To evaluate the estimated vaccine effectiveness (VE) of 2, 3, or 4 doses of COVID-19 mRNA vaccination…
Practice Patterns and Outcomes Associated With Anticoagulation Use Following Sepsis Hospitalizations With New-Onset Atrial Fibrillation
Practice patterns and outcomes associated with the use of oral anticoagulation for arterial thromboembolism prevention following a hospitalization with new-onset atrial fibrillation (AF) during sepsis are unclear. Retrospective, observational cohort study of patients ≥40 years of age discharged alive following…
Perinatal Outcomes After Bariatric Surgery Compared With a Matched Control Group
To evaluate perinatal outcomes associated with pregnancy after bariatric surgery within a large integrated health care system using propensity score matching. We conducted a retrospective cohort study that evaluated perinatal outcomes in pregnant patients after bariatric surgery from January 2012…
Long-term Trajectories of Physical Function Decline in Women With and Without Cancer
Patients with cancer experience acute declines in physical function, hypothesized to reflect accelerated aging driven by cancer-related symptoms and effects of cancer therapies. No study has examined long-term trajectories of physical function by cancer site, stage, or treatment compared with…
Natural history of multiple recurrences in intermediate-risk non-muscle invasive bladder cancer: lessons from a prospective cohort
To describe the risk of multiple recurrences in intermediate-risk non-muscle invasive bladder cancer (IR-NMIBC) and their impact on progression. Prognostic studies of IR-NMIBC have focused on initial recurrences, yet little is known about subsequent recurrences and their impact on progression.…
Maternal SARS-CoV-2 vaccination and infant protection against SARS-CoV-2 during the first six months of life
We examined the effectiveness of maternal vaccination against SARS-CoV-2 infection in 30,311 infants born at Kaiser Permanente Northern California from December 15, 2020, to May 31, 2022. Using Cox regression, the effectiveness of ≥2 doses of COVID-19 vaccine received during…
Protection from COVID-19 mRNA vaccination and prior SARS-CoV-2 infection against COVID-19-associated encounters in adults during Delta and Omicron predominance
Data assessing protection conferred from COVID-19 mRNA vaccination and/or prior SARS-CoV-2 infection during Delta and Omicron predominance periods in the U.S. are limited. This cohort study included persons ≥18 years who had ≥1 healthcare encounter across four health systems and…
Sex- and ethnic-specific patterns in the incidence of hip fracture among older US Asian and non-Hispanic White adults
Asian and Pacific Islander (Asian/PI) adults have lower hip fracture incidence than non-Hispanic White (NHW) adults, but data regarding Asian/PI subgroups are limited. We compared hip fracture incidence among older US Asian/PI and NHW populations, including ethnic subgroup differences. Using…
Maternal and neonatal outcomes associated with treating hypertension in pregnancy at different thresholds
In the United States, there has been controversy over whether treatment of mild-to-moderate hypertension during pregnancy conveys more benefit than risk. The objective of the study was to compare risks and benefits of treatment of mild-to-moderate hypertension during pregnancy. This…
Association of the COVID-19 Pandemic With Unstable and/or Unsafe Living Situations and Intimate Partner Violence Among Pregnant Individuals
The social, behavioral, and economic consequences of the COVID-19 pandemic may be associated with unstable and/or unsafe living situations and intimate partner violence (IPV) among pregnant individuals. To investigate trends in unstable and/or unsafe living situations and IPV among pregnant…
Association of Long-term Exposure to Particulate Air Pollution With Cardiovascular Events in California
Long-term exposure to fine particulate air pollution (PM2.5) is a known risk factor for cardiovascular events, but controversy remains as to whether the current National Ambient Air Quality Standard (12 μg/m3 for 1-year mean PM2.5) is sufficiently protective. To evaluate…
High-dimensional propensity scores for empirical covariate selection in secondary database studies: Planning, implementation, and reporting
Real-world evidence used for regulatory, payer, and clinical decision-making requires principled epidemiology in design and analysis, applying methods to minimize confounding given the lack of randomization. One technique to deal with potential confounding is propensity score (PS) analysis, which allows…
Association of cannabis use during pregnancy with severe acute respiratory syndrome coronavirus 2 infection: a retrospective cohort study
Cannabis use is increasingly common among pregnant individuals and might be a risk factor for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. We aimed to test whether prenatal cannabis use is associated with increased risk of SARS-CoV-2 infection during…
A prospective study of lifestyle factors and bone health in breast cancer patients who received aromatase inhibitors in an integrated healthcare setting
Fracture and osteoporosis are known side effects of aromatase inhibitors (AIs) for postmenopausal hormone receptor positive (HR+) breast cancer (BC) patients. How modifiable lifestyle factors impact fracture risk in these patients is relatively unknown. We conducted a prospective cohort study…
Vaccine effectiveness against influenza-associated urgent care, emergency department, and hospital encounters during the 2021-2022 season, VISION Network
Following historically low influenza activity during the 2020-2021 season, the United States saw an increase in influenza circulating during the 2021-2022 season. Most viruses belonged to the influenza A(H3N2) 3C.2a1b 2a.2 subclade. We conducted a test-negative case-control analysis among adults…
MiXcan: a framework for cell-type-aware transcriptome-wide association studies with an application to breast cancer
Human bulk tissue samples comprise multiple cell types with diverse roles in disease etiology. Conventional transcriptome-wide association study approaches predict genetically regulated gene expression at the tissue level, without considering cell-type heterogeneity, and test associations of predicted tissue-level expression with…
A broad assessment of covid-19 vaccine safety using tree-based data-mining in the vaccine safety datalink
Except for spontaneous reporting systems, vaccine safety monitoring generally involves pre-specifying health outcomes and post-vaccination risk windows of concern. Instead, we used tree-based data-mining to look more broadly for possible adverse events after Pfizer-BioNTech, Moderna, and Janssen COVID-19 vaccination. Vaccine…
A safety study evaluating non-COVID-19 mortality risk following COVID-19 vaccination
The safety of COVID-19 vaccines plays an important role in addressing vaccine hesitancy. We conducted a large cohort study to evaluate the risk of non-COVID-19 mortality after COVID-19 vaccination while adjusting for confounders including individual-level demographics, clinical risk factors, health…
A mid-level health manager intervention to promote uptake of isoniazid preventive therapy among people with HIV in Uganda: a cluster randomised trial.
BACKGROUND: Despite longstanding guidelines endorsing isoniazid preventive therapy (IPT) for people with HIV, uptake is low across sub-Saharan Africa. Mid-level health managers oversee IPT programmes nationally; interventions aimed at this group have not been tested. We aimed to establish whether…
HIV incidence after pre-exposure prophylaxis initiation among women and men at elevated HIV risk: A population-based study in rural Kenya and Uganda.
BACKGROUND: Oral pre-exposure prophylaxis (PrEP) is highly effective for HIV prevention, but data are limited on HIV incidence among PrEP users in generalized epidemic settings, particularly outside of selected risk groups. We performed a population-based PrEP study in rural Kenya…
Type I error control for cluster randomized trials under varying small sample structures.
BACKGROUND: Linear mixed models (LMM) are a common approach to analyzing data from cluster randomized trials (CRTs). Inference on parameters can be performed via Wald tests or likelihood ratio tests (LRT), but both approaches may give incorrect Type I error…
Tree-based data mining for safety assessment of first COVID-19 booster doses in the Vaccine Safety Datalink
The Centers for Disease Control and Prevention's Vaccine Safety Datalink (VSD) has been performing safety surveillance for COVID-19 vaccines since their earliest authorization in the United States. Complementing its real-time surveillance for pre-specified health outcomes using pre-specified risk intervals, the…
Cigarette Smoking and Risk of SARS-CoV-2 infection and Disease Severity Among Adults in an Integrated Health Care System in California
The relationship between tobacco smoking status and SARS-CoV-2 infection and coronavirus disease 2019 (COVID-19) severity is highly debated. We conducted a retrospective cohort study of?>2.4 million adults in a large healthcare system to evaluate whether smoking is associated with SARS-CoV-2…
Pregnancy post-bariatric surgery: Improved outcomes with telephonic nutritional management program
Pregnancies post-bariatric surgery are increasingly common. It is important to understand how to manage prenatal care in this high-risk population to optimize perinatal outcomes. To determine among pregnancies post-bariatric surgery whether participation in a telephonic nutritional management program was associated…
Association between anaemia and hospital readmissions in patients undergoing major surgery requiring postoperative intensive care
Anaemia is a common sequela of surgery, although its relationship with patient recovery is unclear. The goal of this investigation was to assess the associations between haemoglobin concentrations at the time of hospital discharge following major surgery and early post-hospitalisation…
Survival Associated With Consolidated Multidisciplinary Care in Head and Neck Cancer: A Retrospective Cohort Study
To compare survival among patients with head and neck cancer before and after implementing a weekly multidisciplinary clinic and case conference. A retrospective cohort study with chart review was conducted of 3081 patients (1431 preimplementation, 1650 postimplementation) diagnosed with stage…
An application of the Causal Roadmap in two safety monitoring case studies: Causal inference and outcome prediction using electronic health record data
Real-world data, such as administrative claims and electronic health records, are increasingly used for safety monitoring and to help guide regulatory decision-making. In these settings, it is important to document analytic decisions transparently and objectively to assess and ensure that…
Early Estimates of Bivalent mRNA Vaccine Effectiveness in Preventing COVID-19-Associated Emergency Department or Urgent Care Encounters and Hospitalizations Among Immunocompetent Adults – VISION Network, Nine States, September-November 2022
During June-October 2022, the SARS-CoV-2 Omicron BA.5 sublineage accounted for most of the sequenced viral genomes in the United States, with further Omicron sublineage diversification through November 2022.* Bivalent mRNA vaccines contain an ancestral SARS-CoV-2 strain component plus an updated…
Metabolic abnormalities and survival among patients with non-metastatic breast cancer
Research on the impact of metabolic abnormalities on breast cancer prognosis is limited by small samples and assessment of laboratory values at a single time point, often prior to cancer diagnosis and treatment. In this population-based cohort, time-updated laboratory values…
Trends in Self-reported and Biochemically Verified Cocaine and Methamphetamine Use Among Pregnant Individuals in Northern California, 2011-2019
This cross-sectional study uses data from the Kaiser Permanente Northern California health care system with universal screening via self-report and urine toxicology at prenatal care entrance to examine trends in cocaine and methamphetamine use among pregnant individuals from 2011 to…
High-sensitivity troponin I is associated with cardiovascular outcomes but not with breast arterial calcification among postmenopausal women
Prior studies support the utility of high sensitivity troponin I (hsTnI) for cardiovascular disease (CVD) risk stratification among asymptomatic populations; however, only two prior studies examined women separately. The association between hsTnI and breast arterial calcification is unknown. Cohort study…
Demographic, Reproductive, and Medical Risk Factors for Intrauterine Device Expulsion
To explore to what extent intrauterine device (IUD) expulsion is associated with demographic and clinical risk factors. The APEX-IUD (Association of Perforation and Expulsion of IntraUterine Devices) study was a U.S. cohort study using electronic health records from three integrated…
Urinary Phenols in Early to Mid-Pregnancy and Risk of Gestational Diabetes: A Longitudinal Study in a Multiracial Cohort
Environmental phenols are ubiquitous endocrine disruptors and putatively diabetogenic. However, data during pregnancy are scant. We investigated the prospective associations between pregnancy phenol concentrations and gestational diabetes mellitus (GDM) risk. In a nested matched case-control study of 111 individuals with…
A large genome-wide association study of QT interval length utilizing electronic health records
QT interval length is an important risk factor for adverse cardiovascular outcomes; however, the genetic architecture of QT interval remains incompletely understood. We conducted a genome-wide association study of 76,995 ancestrally diverse Kaiser Permanente Northern California members enrolled in the…
Nugent, Joshua R.
Marafino, Ben J.
Lee, Catherine
Neugebauer, Romain S.
Fireman, Bruce H.
Alexeeff, Stacey
Armstrong, Mary Anne
Associations between childhood obesity and pubertal timing stratified by sex and race/ethnicity
Earlier puberty has been associated with numerous adverse mental, emotional, and physical health outcomes. Obesity is a known risk factor for earlier puberty in girls, but research with boys has yielded inconsistent findings. We examined sex- and race/ethnicity-specific associations between…
Association of serum folate levels during pregnancy and prenatal depression
To evaluate the association between serum folate levels during pregnancy and prenatal depression and the extent to which obesity may modify this relationship. This secondary data analysis leveraged data from a previous study of pregnant Kaiser Permanente Northern California participants…
Smoking Behaviors and Prognosis in Patients With Non-Muscle-Invasive Bladder Cancer in the Be-Well Study
Tobacco smoking is an established risk factor associated with bladder cancer, yet its impact on bladder cancer prognosis is unclear. To examine associations of use of tobacco (cigarettes, pipes, and cigars), e-cigarettes, and marijuana with risk of recurrence and progression…
Geographic Accessibility of Retail Cannabis in Northern California and Prenatal Cannabis Use During the COVID-19 Pandemic
Prenatal cannabis use is associated with health risks for mothers and their children. Prior research suggests that rates of prenatal cannabis use in Northern California increased during the COVID-19 pandemic, but it is unknown whether increases varied with the local…
Association of Thoracic Aortic Aneurysm Size With Long-term Patient Outcomes: The KP-TAA Study
The risk of adverse events from ascending thoracic aorta aneurysm (TAA) is poorly understood but drives clinical decision-making. To evaluate the association of TAA size with outcomes in nonsyndromic patients in a large non-referral-based health care delivery system. The Kaiser…
Retrospective cohort study to assess the association between treatment with tocilizumab and mortality among mechanically ventilated patients with COVID-19
Assess the association between tocilizumab administration and clinical outcomes among mechanically ventilated patients with COVID-19 pneumonia. Retrospective cohort study. Large integrated health system with 9 million members in California, USA. 4185 Kaiser Permanente members hospitalised with COVID-19 pneumonia requiring invasive mechanical…
Prescribing for different antibiotic classes across age groups in the Kaiser Permanente Northern California population in association with influenza incidence, 2010-2018
There is limited information on the volume of antibiotic prescribing that is influenza-associated, resulting from influenza infections and their complications (such as streptococcal pharyngitis). We estimated that for the Kaiser Permanente Northern California population during 2010-2018, 3.4% (2.8%-4%) of all…
Effectiveness of COVID-19 mRNA Vaccines Against COVID-19-Associated Hospitalizations Among Immunocompromised Adults During SARS-CoV-2 Omicron Predominance – VISION Network, 10 States, December 2021-August 2022
Persons with moderate-to-severe immunocompromising conditions might have reduced protection after COVID-19 vaccination, compared with persons without immunocompromising conditions (1-3). On August 13, 2021, the Advisory Committee on Immunization Practices (ACIP) recommended that adults with immunocompromising conditions receive an expanded primary…
Maternal SARS-CoV-2 Vaccination and Infant Protection Against SARS-CoV-2 During the First 6 Months of Life
We examined the effectiveness of maternal vaccination against SARS-CoV-2 infection in 30,288 infants born at Kaiser Permanente Northern California from December 15, 2020, to May 31, 2022. Using Cox regression, the effectiveness of maternal vaccination was 85% (95% confidence interval…
Patterns of Substance Use During Early Pregnancy and Associations With Behavioral Health Characteristics
The aims of the study are to identify patterns of early pregnancy substance use and to examine how these patterns relate to behavioral health conditions measured in early pregnancy. We conducted a retrospective observational study (N= 265,274 pregnancies) screened for…
Assessment of genetic susceptibility to multiple primary cancers through whole-exome sequencing in two large multi-ancestry studies
Up to one of every six individuals diagnosed with one cancer will be diagnosed with a second primary cancer in their lifetime. Genetic factors contributing to the development of multiple primary cancers, beyond known cancer syndromes, have been underexplored. To…
Waning of vaccine effectiveness against moderate and severe covid-19 among adults in the US from the VISION network: test negative, case-control study
To estimate the effectiveness of mRNA vaccines against moderate and severe covid-19 in adults by time since second, third, or fourth doses, and by age and immunocompromised status. Test negative case-control study. Hospitals, emergency departments, and urgent care clinics in…
Sociodemographic and clinical characteristics associated with never-smoking status in patients with lung cancer: findings from a large integrated health system
Evidence is limited characterizing sociodemographically diverse patient populations with lung cancer in relation to smoking status. In a cross-sectional analysis of adults diagnosed with lung cancer at ages ≥30 years from 2007-2018 within an integrated healthcare system, overall and sex-specific…
Disparities in the Incidence of Ectopic Pregnancy in a Large Health Care System in California, 2010-2019
IntroductionEctopic pregnancy leads to reproductive health morbidity, including greater risk of another ectopic pregnancy, infertility, and, in rare cases, mortality. Information on trends in the incidence of ectopic pregnancy in the last decade is limited. MethodsA population-based cross-sectional study of…
Estimation of COVID-19 mRNA Vaccine Effectiveness Against Medically Attended COVID-19 in Pregnancy During Periods of Delta and Omicron Variant Predominance in the United States
Pregnant people are at high risk for severe COVID-19 but were excluded from mRNA vaccine trials; data on COVID-19 vaccine effectiveness (VE) are needed. To evaluate the estimated effectiveness of mRNA vaccination against medically attended COVID-19 among pregnant people during…
Electronic cigarette use and risk of COVID-19 among young adults without a history of cigarette smoking
It is unknown whether use of e-cigarettes increases susceptibility to COVID-19. In a large clinical sample of young adults, we evaluated whether current or ever e-cigarette use was associated with polymerase chain reaction (PCR)-confirmed COVID-19. To address the confounding of…
Maternal autoantibody profiles as biomarkers for ASD and ASD with co-occurring intellectual disability
Maternal autoantibody-related ASD (MAR ASD) is a subtype of autism in which pathogenic maternal autoantibodies (IgG) cross the placenta, access the developing brain, and cause neurodevelopmental alterations and behaviors associated with autism in the exposed offspring. We previously reported maternal…
Risk of myocarditis and pericarditis following BNT162b2 and mRNA-1273 COVID-19 vaccination
Evidence indicates that mRNA COVID-19 vaccination is associated with risk of myocarditis and possibly pericarditis, especially in young males. It is not clear if risk differs between mRNA-1273 versus BNT162b2. We assessed if risk differs using comprehensive health records on…
Prolactin and maternal metabolism in women with a recent GDM pregnancy and links to future T2D: the SWIFT study
Prolactin is a multifaceted hormone known to regulate lactation. In women with gestational diabetes mellitus (GDM) history, intensive lactation has been associated with lower relative risk of future type 2 diabetes (T2D). However, the role of prolactin in T2D development…
Risk of severe COVID-19 infection among adults with prior exposure to children
Susceptibility and severity of COVID-19 infection vary widely. Prior exposure to endemic coronaviruses, common in young children, may protect against SARS-CoV-2. We evaluated risk of severe COVID-19 among adults with and without exposure to young children in a large, integrated…
Safety of COVID-19 Vaccination in US Children Ages 5-11 Years
Limited postauthorization safety data for the Pfizer-BioNTech coronavirus disease 2019 vaccination among children ages 5 to 11 years are available, particularly for the adverse event myocarditis, which has been detected in adolescents and young adults. We describe adverse events observed…
Predictive Metabolomic Markers in Early to Mid-Pregnancy for Gestational Diabetes: A Prospective Test and Validation Study
Gestational diabetes mellitus (GDM) predisposes pregnant individuals to perinatal complications and long-term diabetes and cardiovascular diseases. We developed and validated metabolomic markers for GDM in a prospective test-validation study. In a case-control sample within the PETALS cohort (GDM n =…
Adults hospitalized with breakthrough COVID-19 have lower mortality than matched unvaccinated adults
Coronavirus disease 2019 (COVID-19) breakthrough infections are common. Evaluate in-hospital mortality of patients with COVID-19 by vaccination status using retrospective cohort study. We generated propensity scores for receipt of full vaccination in adults requiring supplemental oxygen hospitalized at Kaiser Permanente…
Myocarditis and/or pericarditis risk after mRNA COVID-19 vaccination: A Canadian head to head comparison of BNT162b2 and mRNA-1273 vaccines
Canadian and international data suggest the risk of myocarditis and/or pericarditis is elevated during the week after mRNA COVID-19 vaccination, particularly in younger age groups, in males, and after second doses. This article examines whether there is a product-specific difference…
Effectiveness of 2, 3, and 4 COVID-19 mRNA Vaccine Doses Among Immunocompetent Adults During Periods when SARS-CoV-2 Omicron BA.1 and BA.2/BA.2.12.1 Sublineages Predominated – VISION Network, 10 States, December 2021-June 2022
The Omicron variant (B.1.1.529) of SARS-CoV-2, the virus that causes COVID-19, was first identified in the United States in November 2021, with the BA.1 sublineage (including BA.1.1) causing the largest surge in COVID-19 cases to date. Omicron sublineages BA.2 and…
Reach, acceptability, and perceived success of a telehealth diabetes prevention program among racially and ethnically diverse patients with gestational diabetes: the GEM cluster-randomized trial
Patients with gestational diabetes mellitus and from racial/ethnic minority groups face disproportionate risk for type 2 diabetes. Lifestyle interventions, if accessible and acceptable to diverse patients, could advance diabetes prevention and mitigate racial/ethnic disparities. Here we describe overall and race/ethnicity-specific…
Association Between Intrauterine Device Type and Risk of Perforation and Device Expulsion: Results From the APEX-IUD Study
Intrauterine devices, including levonorgestrel-releasing and copper devices, are highly effective long-acting reversible contraceptives. The potential risks associated with intrauterine devices are low and include uterine perforation and device expulsion. This study aimed to evaluate the risk of perforation and expulsion…
Association Between Menorrhagia and Risk of Intrauterine Device-Related Uterine Perforation and Device Expulsion: Results from the APEX-IUD Study
Intrauterine devices are effective instruments for contraception, and 1 levonorgestrel-releasing device is also indicated for the treatment of heavy menstrual bleeding (menorrhagia). To compare the incidence of intrauterine device expulsion and uterine perforation in women with and without a diagnosis…
Lessons from a mature acellular pertussis vaccination program and strategies to overcome suboptimal vaccine effectiveness
Despite high vaccination coverage among children and adolescents, pertussis remains a public health problem, with large outbreaks occurring periodically in the US and other developed countries. We examine lessons learned more than 20 years after implementation of programs which use only…
Prevalence of Depression and Anxiety Disorders Following Mild Traumatic Brain Injury
Previous studies have identified an association between traumatic brain injuries and the development of psychiatric disorders in general. However, these studies were subject to limitations that demonstrate the need for a study of a large, clearly defined mild traumatic brain…
A Web-Based mHealth Intervention With Telephone Support to Increase Physical Activity Among Pregnant Patients With Overweight or Obesity: Feasibility Randomized Controlled Trial
Pregnant patients with overweight or obesity are at high risk for perinatal complications. Excess gestational weight gain (GWG) further exacerbates this risk. Mobile health (mHealth) lifestyle interventions that leverage technology to facilitate self-monitoring and provide just-in-time feedback may motivate behavior…
Risk of severe clinical outcomes among persons with SARS-CoV-2 infection with differing levels of vaccination during widespread Omicron (B.1.1.529) and Delta (B.1.617.2) variant circulation in Northern California: A retrospective cohort study
The incidence of and risk factors for severe clinical outcomes with the Omicron (B.1.1.529) SARS-CoV-2 variant have not been well-defined. We conducted a retrospective cohort study to assess risks of severe clinical outcomes within 21 days after SARS-CoV-2 diagnosis in…
Association of Physician Adenoma Detection Rates With Postcolonoscopy Colorectal Cancer
Although colonoscopy is frequently performed in the United States, there is limited evidence to support threshold values for physician adenoma detection rate as a quality metric. To evaluate the association between physician adenoma detection rate values and risks of postcolonoscopy…
Intrauterine device-related uterine perforation incidence and risk (APEX-IUD): a large multisite cohort study
Reports of perforation risk related to intrauterine devices (IUDs) inserted immediately post partum and among non-post-partum individuals are scarce, and previous studies with only 12-month follow-ups underestimate the risk. Breastfeeding at IUD insertion and insertion within 36 weeks post partum…
Uptake of guideline-recommended postpartum diabetes screening among diverse women with gestational diabetes: associations with patient factors in an integrated health system in USA
Clinical guidelines urge timely postpartum screening for diabetes among women with gestational diabetes mellitus (GDM), yet patient factors associated with screening uptake remain unclear. We aimed to identify patient factors associated with completed postpartum diabetes screening (2-hour oral glucose tolerance…
Effect of Electronic and Mail Outreach From Primary Care Physicians for COVID-19 Vaccination of Black and Latino Older Adults: A Randomized Clinical Trial
COVID-19 morbidity is highest in Black and Latino older adults. These racial and ethnic groups initially had lower vaccination uptake than others, and rates in Black adults continue to lag. To evaluate the effect of outreach via electronic secure messages…
Trends in Cannabis Polysubstance Use During Early Pregnancy Among Patients in a Large Health Care System in Northern California
Rates of prenatal cannabis use are increasing alongside perceptions that cannabis is a harmless therapeutic for pregnancy-related ailments, while rates of prenatal use of alcohol and tobacco are decreasing. It is important to examine whether cannabis use during pregnancy is…
Predicting obstructive sleep apnea severity in children referred for polysomnography: use of the Pediatric Sleep Questionnaire and Subscales
This study evaluated the role of the Pediatric Sleep Questionnaire (PSQ) and associated subscales in predicting the severity of obstructive sleep apnea (OSA) in children referred for attended polysomnography (PSG). This is a retrospective study of children (0-18 years) who completed…
Risk of Cardiovascular Disease in Women With and Without Breast Cancer: The Pathways Heart Study
To examine cardiovascular disease (CVD) and mortality risk in women with breast cancer (BC) by cancer therapy received relative to women without BC. The study population comprised Kaiser Permanente Northern California members. Cases with invasive BC diagnosed from 2005 to…
Risk of Cardiometabolic Risk Factors in Women With and Without a History of Breast Cancer: The Pathways Heart Study
The incidence of cardiometabolic risk factors in breast cancer (BC) survivors has not been well described. Thus, we compared risk of hypertension, diabetes, and dyslipidemia in women with and without BC. Women with invasive BC diagnosed from 2005 to 2013…
Exploratory analysis of novel electronic health record variables for quantification of healthcare delivery strain, prediction of mortality, and prediction of imminent discharge
To explore the relationship between novel, time-varying predictors for healthcare delivery strain (eg, counts of patient orders per hour) and imminent discharge and in-hospital mortality. We conducted a retrospective cohort study using data from adults hospitalized at 21 Kaiser Permanente…
Effect of Lifestyle Coaching or Enhanced Pharmacotherapy on Blood Pressure Control Among Black Adults With Persistent Uncontrolled Hypertension: A Cluster Randomized Clinical Trial
Greater difficulty in controlling blood pressure (BP) and adverse lifestyle practices such as higher salt intake or less physical activity may account for some of the differences between BP control rates in Black vs White adults, thereby exposing Black adults…
Contribution of Maternal Cardiometabolic Risk Factors to Racial-Ethnicity Disparities in Preterm Birth Subtypes
There are recognized racial-ethnic disparities in preterm birth and in maternal cardiometabolic risk factors likely linked to systemic racism. However, it is unclear the extent to which cardiometabolic risk factors contribute to the higher rates of preterm birth among minoritized…
Association between residential green cover and direct healthcare costs in Northern California: An individual level analysis of 5 million persons
Prior studies have shown higher green cover levels are associated with beneficial health outcomes. We sought to determine if residential green cover was also associated with direct healthcare costs. We linked residential Normalized Difference Vegetation Index (NDVI) satellite data for…
Perinatal Complications in Individuals in California With or Without SARS-CoV-2 Infection During Pregnancy
Additional research from population-based studies is needed to inform the treatment of SARS-CoV-2 infection during pregnancy and to provide health risk information to pregnant individuals. To assess the risk of perinatal complications associated with SARS-CoV-2 infection and to describe factors…
Safety of measles and pertussis-containing vaccines in children with autism spectrum disorders
To determine whether children aged 4-7 years with a diagnosis of autism spectrum disorders (ASD) were at increased risk of fever, febrile seizures, or emergency department (ED) visits following measles- or pertussis-containing vaccines compared with children without ASD. The study included…
Incidence of Guillain-Barré Syndrome After COVID-19 Vaccination in the Vaccine Safety Datalink
Postauthorization monitoring of vaccines in a large population may detect rare adverse events not identified in clinical trials such as Guillain-Barré syndrome (GBS), which has a background rate of 1 to 2 per 100 000 person-years. To describe cases and incidence…
Joint associations between neighborhood walkability, greenness, and particulate air pollution on cardiovascular mortality among adults with a history of stroke or acute myocardial infarction
Fine particulate matter (PM2.5) is a known risk factor for cardiovascular disease (CVD). Neighborhood walkability and greenness may also be associated with CVD, but there is limited evidence on their joint or interacting effects with PM2.5. Cox proportional hazard models…
Effectiveness of Homologous and Heterologous COVID-19 Booster Doses Following 1 Ad.26.COV2.S (Janssen [Johnson & Johnson]) Vaccine Dose Against COVID-19-Associated Emergency Department and Urgent Care Encounters and Hospitalizations Among Adults – VISION Network, 10 States, December 2021-March 2022
CDC recommends that all persons aged ≥18 years receive a single COVID-19 vaccine booster dose ≥2 months after receipt of an Ad.26.COV2.S (Janssen [Johnson & Johnson]) adenovirus vector-based primary series vaccine; a heterologous COVID-19 mRNA vaccine is preferred over a…
Primary care telemedicine during the COVID-19 pandemic: patient’s choice of video versus telephone visit
The aim of this study is to examine the association between patient characteristics and primary care telemedicine choice among integrated delivery system patients self-scheduling visits during the COVID-19 pandemic. We used multivariate logistic regression to examine the association between the…
Association of teledermatology workflows with standardising co-management of rashes by primary care physicians and dermatologists
For patients with a rash, the effect of teledermatology workflow on utilization has not been defined. We compared utilization across four teledermatology workflows in patients with a rash. The observational longitudinal cohort study included 28,857 Kaiser Permanente Northern California members…
Associations between infant growth and pubertal onset timing in a multiethnic prospective cohort of girls
Early puberty increases risk of adverse health conditions throughout the life course. US girls are experiencing earlier puberty without clear reasons. Studies suggest early life factors, such as infant growth, may influence pubertal timing. We assessed the associations between infant…
Effectiveness of COVID-19 Pfizer-BioNTech BNT162b2 mRNA Vaccination in Preventing COVID-19-Associated Emergency Department and Urgent Care Encounters and Hospitalizations Among Nonimmunocompromised Children and Adolescents Aged 5-17 Years – VISION Network, 10 States, April 2021-January 2022
The efficacy of the BNT162b2 (Pfizer-BioNTech) vaccine against laboratory-confirmed COVID-19 exceeded 90% in clinical trials that included children and adolescents aged 5-11, 12-15, and 16-17 years (1-3). Limited real-world data on 2-dose mRNA vaccine effectiveness (VE) in persons aged 12-17…
Comparison of dementia incidence and prevalence between individuals with and without HIV infection in primary care from 2000 to 2016
To compare dementia incidence and prevalence after age 50 years by HIV status. Observational cohort, 2000-2016. People with HIV (PWH) on antiretroviral therapy (ART) and demographically similar people without HIV (PWoH), all aged 50 years and older, were identified from Kaiser…
Breast Arterial Calcification: a Novel Cardiovascular Risk Enhancer Among Postmenopausal Women
Breast arterial calcification (BAC), a common incidental finding in mammography, has been shown to be associated with angiographic coronary artery disease and cardiovascular disease (CVD) outcomes. We aimed to (1) examine the association of BAC presence and quantity with hard…
Association of Glyburide and Subcutaneous Insulin With Perinatal Complications Among Women With Gestational Diabetes
Nearly 30% of individuals with gestational diabetes (GDM) do not achieve glycemic control with lifestyle modification alone and require medication treatment. Oral agents, such as glyburide, have several advantages over insulin for the treatment of GDM, including greater patient acceptance;…
Early Pregnancy Blood Pressure Patterns Identify Risk of Hypertensive Disorders of Pregnancy Among Racial and Ethnic Groups
Hypertensive disorders of pregnancy are a leading cause of severe maternal morbidity and mortality and confer 4-fold higher perinatal mortality in Black women. Early pregnancy blood pressure patterns may differentiate risk of hypertensive disorders of pregnancy. This study identified distinct…
Impact of the Affordable Care Act on Colorectal Cancer Incidence and Mortality
The Patient Protection and Affordable Care Act eliminated cost sharing for preventive services, including colorectal cancer screening for individuals aged 50-75 years with private health insurance. This study examines the impact of the Affordable Care Act's removal of cost sharing…
Cohort and Nested Case-Control Study of Cutaneous Squamous Cell Carcinoma in Solid Organ Transplant Recipients, by Medication
Knowledge is needed about the risk of cutaneous squamous cell carcinoma (cSCC) in solid organ transplant recipients (SOTRs) using contemporary immunosuppressive regimens. Evaluate the risk of cSCC in relation to medications used by SOTRs. The cohort and nest case-control study…
Antibiotic prescribing across age groups in the Kaiser Permanente Northern California population in association with different diagnoses, and with influenza incidence, 2010-2018
There is limited information on the volume of antibiotic prescribing that is influenza-associated, resulting from influenza infections and their complications (such as streptococcal pharyngitis and otitis media). Here, we estimated age/diagnosis-specific proportions of antibiotic prescriptions (fills) for the Kaiser Permanente…
Waning 2-Dose and 3-Dose Effectiveness of mRNA Vaccines Against COVID-19-Associated Emergency Department and Urgent Care Encounters and Hospitalizations Among Adults During Periods of Delta and Omicron Variant Predominance – VISION Network, 10 States, August 2021-January 2022
CDC recommends that all persons aged ≥12 years receive a booster dose of COVID-19 mRNA vaccine ≥5 months after completion of a primary mRNA vaccination series and that immunocompromised persons receive a third primary dose.* Waning of vaccine protection after…
Impact of wildfire air pollution on rates of cardiovascular events and mortality
There is an increasing frequency of large wildfires in California. Smoke from these wildfires can drastically increase short-term exposure to harmful air pollutants, especially particulate matter (PM), and some KPNC members may be at greater risk of the adverse health…
Understanding the risk of ectopic pregnancies among people seeking abortion: a retrospective case control study
This study aims to assess the incidence of ectopic pregnancy among people wanting pregnancy compared to people seeking abortion. The specific research questions are: Are people seeking abortion at lower risk of experiencing an ectopic pregnancy compared to people not…
Association of the Timing of Postpartum Intrauterine Device Insertion and Breastfeeding With Risks of Intrauterine Device Expulsion
Intrauterine device (IUD) expulsion increases the risk of unintended pregnancy; how timing of postpartum IUD insertion and breastfeeding are associated with risk of expulsion is relevant to the benefit-risk profile. To evaluate the association of postpartum timing of IUD insertion…
Self-controlled assessment of thromboembolic event (TEE) risk following intravenous immune globulin (IGIV) in the U.S. (2006-2012)
Since 2013, the U.S. Food and Drug administration (FDA) has required that intravenous immune globulin (IGIV) products carry a boxed warning concerning the risk of thromboembolic events (TEEs). This study assessed the incidence of TEEs attributable to IGIV in a…
Effectiveness of a Third Dose of mRNA Vaccines Against COVID-19-Associated Emergency Department and Urgent Care Encounters and Hospitalizations Among Adults During Periods of Delta and Omicron Variant Predominance – VISION Network, 10 States, August 2021-January 2022
Estimates of COVID-19 mRNA vaccine effectiveness (VE) have declined in recent months (1,2) because of waning vaccine induced immunity over time,* possible increased immune evasion by SARS-CoV-2 variants (3), or a combination of these and other factors. CDC recommends that…
TP53 Gain-of-Function and Non-Gain-of-Function Mutations Are Differentially Associated With Sidedness-Dependent Prognosis in Metastatic Colorectal Cancer
To examine the association of gain-of-function (GOF) and non-gain-of-function (non-GOF) TP53 mutations with prognosis of metastatic right-sided (RCC) versus left-sided colorectal cancer (LCC). This cohort study included patients with metastatic colorectal cancer (CRC) who had next-generation sequencing performed from November…
Identifying hypertensive disorders of pregnancy, a comparison of two epidemiologic definitions
Studies of hypertension in pregnancy that use electronic health care data generally identify hypertension using hospital diagnosis codes alone. We sought to compare results from this approach to an approach that included diagnosis codes, antihypertensive medications and blood pressure (BP)…
Maternal and neonatal outcomes of antihypertensive treatment in pregnancy: A retrospective cohort study
To compare maternal and infant outcomes with different antihypertensive medications in pregnancy. Retrospective cohort study. Kaiser Permanente, a large healthcare system in the United States. Women aged 15-49 years with a singleton birth from 2005-2014 treated for hypertension. We identified…
Rates of cardiovascular events among patients with moderate-to-severe atopic dermatitis in an integrated health care system: A retrospective cohort study
Patients with versus without atopic dermatitis may have a greater risk of cardiovascular events, and the risk increases with severity of atopic dermatitis. The incidence of cardiovascular events in the population of patients with moderate-to-severe atopic dermatitis is largely unknown.…
Parent-focused prevention of adolescent health risk behavior: Study protocol for a multisite cluster-randomized trial implemented in pediatric primary care
Evidence-based parenting interventions play a crucial role in the sustained reduction of adolescent behavioral health concerns. Guiding Good Choices (GGC) is a 5-session universal anticipatory guidance curriculum for parents of early adolescents that has been shown to reduce substance use,…
Ectopic Pregnancy Prevention: Further Evidence of Benefits of Prescription Contraceptives
To estimate the incidence of ectopic pregnancy (EP) associated with prescription contraceptive use. We performed a retrospective cohort study of women aged 15 to 44 years at Kaiser Permanente Northern and Southern California during 2010 to 2019. We identified EPs…
Torsade de pointes: A nested case-control study in an integrated healthcare delivery system
TdP is a form of polymorphic ventricular tachycardia which develops in the setting of a prolonged QT interval. There are limited data describing risk factors, treatment, and outcomes of this potentially fatal arrhythmia. Our goals were as follows: (1) to…
Population-based assessment of risks for severe COVID-19 disease outcomes
Among approximately 4.6 million members of Kaiser Permanente Northern California, we examined associations of severe COVID-19 with demographic factors and comorbidities. As of July 23, 2021, 16 182 had been hospitalized, 2416 admitted to an ICU, and 1525 died due to…
Predicting adolescent alcohol and other drug problems using electronic health records data
Alcohol and other drug (AOD) use problems may cause significant burden on affected adolescents and their families, yet treatment providers often do not identify these problems early enough. To develop, and internally and externally validate a multivariable prediction model of…
Comanagement of Rashes by Primary Care Providers and Dermatologists: A Retrospective Study
There is a high demand for managing skin disease, and dermatologists are in short supply. To better understand how rashes and other specific skin conditions are co-managed by primary care providers (PCPs) and dermatologists, we estimated the frequency with which…
Cancer in people with and without hepatitis C virus infection: comparison of risk before and after introduction of direct-acting antivirals
Chronic hepatitis C virus (HCV) infection is a leading cause of liver cancer. The association of HCV infection with extrahepatic cancers, and the impact of direct-acting antiviral (DAA) treatment on these cancers, is less well known. We conducted a cohort…
Hypotonic-hyporesponsive Episodes After Diphtheria, Tetanus and Acellular Pertussis Vaccination
Hypotonic-hyporesponsive episode (HHE) after whole cell pertussis vaccination is a known adverse event. Less is known about the risk of HHE after administration of acellular pertussis vaccines. Using parental interviews, this study actively surveyed for HHE among infants after doses…
Laboratory-Confirmed COVID-19 Among Adults Hospitalized with COVID-19-Like Illness with Infection-Induced or mRNA Vaccine-Induced SARS-CoV-2 Immunity – Nine States, January-September 2021
Previous infection with SARS-CoV-2 (the virus that causes COVID-19) or COVID-19 vaccination can provide immunity and protection from subsequent SARS-CoV-2 infection and illness. CDC used data from the VISION Network* to examine hospitalizations in adults with COVID-19-like illness and compared…
Effectiveness of 2-Dose Vaccination with mRNA COVID-19 Vaccines Against COVID-19-Associated Hospitalizations Among Immunocompromised Adults – Nine States, January-September 2021
Immunocompromised persons, defined as those with suppressed humoral or cellular immunity resulting from health conditions or medications, account for approximately 3% of the U.S. adult population (1). Immunocompromised adults are at increased risk for severe COVID-19 outcomes (2) and might…
Treatment and Follow-up Care Associated With Patient-Scheduled Primary Care Telemedicine and In-Person Visits in a Large Integrated Health System
Telemedicine visits can offer patients convenient access to a clinician, but it is unclear whether treatment differs from that with in-person visits or how often patients require in-person follow-up. To examine whether physician prescribing and orders differ between telemedicine and…
Prospective validation of the Kaiser Permanente prostate cancer risk calculator in a contemporary, racially diverse, referral population
To prospectively validate a new prostate cancer risk calculator in a racially diverse population. We recently developed, internally validated and published the Kaiser Permanente Prostate Cancer Risk Calculator. This study is a prospective validation of the calculator in a separate,…
Surveillance for Adverse Events After COVID-19 mRNA Vaccination
Safety surveillance of vaccines against COVID-19 is critical to ensure safety, maintain trust, and inform policy. To monitor 23 serious outcomes weekly, using comprehensive health records on a diverse population. This study represents an interim analysis of safety surveillance data…
Intensive lactation among women with recent gestational diabetes significantly alters the early postpartum circulating lipid profile: the SWIFT study
Women with a history of gestational diabetes mellitus (GDM) have a 7-fold higher risk of developing type 2 diabetes (T2D). It is estimated that 20-50% of women with GDM history will progress to T2D within 10 years after delivery. Intensive lactation could…
Effectiveness of Covid-19 Vaccines in Ambulatory and Inpatient Care Settings
There are limited data on the effectiveness of the vaccines against symptomatic coronavirus disease 2019 (Covid-19) currently authorized in the United States with respect to hospitalization, admission to an intensive care unit (ICU), or ambulatory care in an emergency department…
QT Interval Dynamics and Cardiovascular Outcomes: A Cohort Study in an Integrated Health Care Delivery System
Background Long QT has been associated with ventricular dysrhythmias, cardiovascular disease (CVD) mortality, and sudden cardiac death. However, no studies to date have investigated the dynamics of within-person QT change over time in relation to risk of incident CVD and…
Hydrochlorothiazide and risk of melanoma subtypes
Hydrochlorothiazide (HCTZ), a common diuretic known to be photosensitizing and previously associated with non-melanoma skin cancer, was recently reported to be associated with two melanoma subtypes, nodular and lentigo, among residents of Denmark. Our goal was to examine whether Danish…
Association of Cardiovascular Outcomes and Mortality With Sustained Long-Acting Insulin Only vs Long-Acting Plus Short-Acting Insulin Treatment
Cardiovascular events and mortality are the principal causes of excess mortality and health care costs for people with type 2 diabetes. No large studies have specifically compared long-acting insulin alone with long-acting plus short-acting insulin with regard to cardiovascular outcomes.…
Lifestyle-related education and counseling resource utilization and cardiovascular biomarkers in midlife women with low physical activity
Health plan-based resources are promising avenues for decreasing cardiovascular disease risk. This study examined associations of lifestyle-related resource utilization within a healthcare delivery system and cardiovascular biomarkers among midlife women with low physical activity. Midlife women (45-55 years old) with
Healthy preconception and early-pregnancy lifestyle and risk of preterm birth: a prospective cohort study
Preterm birth (PTB) remains a leading cause of neonatal mortality and long-term morbidity. Individual factors have been linked to PTB risk. The impact of a healthy lifestyle, with multiple modifiable prenatal factors, remains unknown. We aimed to examine the associations…
Comparison of type 2 diabetes pharmacotherapy regimens using targeted learning
This study is designed to help patients with type 2 diabetes and their clinicians identify which glucose-lowering medications among SGLT2 inhibitors, GLP-1 receptor agonists, DPP4 inhibitors, or Sulfonylureas have the most favorable effects on heart health and other patient-important outcomes;…
COVID-19 Vaccination Coverage Among Insured Persons Aged ≥16 Years, by Race/Ethnicity and Other Selected Characteristics – Eight Integrated Health Care Organizations, United States, December 14, 2020-May 15, 2021
COVID-19 vaccination is critical to ending the COVID-19 pandemic. Members of minority racial and ethnic groups have experienced disproportionate COVID-19-associated morbidity and mortality (1); however, COVID-19 vaccination coverage is lower in these groups (2). CDC used data from CDC's Vaccine…
Particulate Matter and Cardiovascular Risk in Adults with Chronic Obstructive Pulmonary Disease
Rationale: People with chronic obstructive pulmonary disease (COPD) have an increased risk of cardiovascular disease and may be more susceptible to air pollution exposure. However, no study has examined the association between long-term fine particulate matter exposure (≤2.5 μm in…
Mediating Effects of Cardiometabolic Risk Factors on the Association Between Maternal Race-Ethnicity and Cesarean Delivery Among Low-Risk Women
Background: While racial-ethnic disparities in cesarean delivery rates among nulliparous women delivering a term singleton in the vertex position (NTSV) exist, it remains unclear the extent to which potentially modifiable maternal cardiometabolic risk factors (obesity, maternal hyperglycemia and hypertensive disorders)…
Separating Algorithms from Questions and Causal Inference with Unmeasured Exposures: An Application to Birth Cohort Studies of Early BMI Rebound
Observational studies reporting on adjusted associations between childhood body mass index (BMI; weight (kg)/height (m)2) rebound and subsequent cardiometabolic outcomes have often not paid explicit attention to causal inference, including definition of a target causal effect and assumptions for unbiased…
Visual Outcomes After Cataract Surgery: Topical NSAID Prophylaxis Compared with Prednisolone
To compare visual outcomes in patients without a history of macular edema after phacoemulsification using combination topical nonsteroidal anti-inflammatory drug plus prednisolone with prednisolone alone. Kaiser Permanente Northern California, USA. Retrospective cohort study. Information was obtained from the electronic health…
Participant education, spousal education and dementia risk in a diverse cohort of members of an integrated health care delivery system in Northern California
The role of spousal education on dementia risk and how it may differ by gender or race/ethnicity is unknown. This study examines the association between one's own education separate from and in conjunction with spousal education and risk of dementia.…
Association of Type 1 Diabetes and Hypoglycemic and Hyperglycemic Events and Risk of Dementia
To determine whether severe hypoglycemic and hyperglycemic events are associated with longitudinal dementia risk in older adults with type 1 diabetes. A longitudinal cohort study followed 2,821 members of an integrated healthcare delivery system with type 1 diabetes from 1997-2015.…
A prognostic information system for real-time personalized care: Lessons for embedded researchers
Embedded researchers could play a central role in developing tools to personalize care using electronic medical records (EMRs). However, few studies have described the steps involved in developing such tools, or evaluated the key factors in success and failure. This…
Racial Disparities in COVID-19 Testing and Outcomes : Retrospective Cohort Study in an Integrated Health System
Racial disparities exist in outcomes after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. To evaluate the contribution of race/ethnicity in SARS-CoV-2 testing, infection, and outcomes. Retrospective cohort study (1 February 2020 to 31 May 2020). Integrated health care delivery…
Design of the Association of Uterine Perforation and Expulsion of IUD (APEX-IUD) Study: A Multisite Retrospective Cohort Study
Intrauterine devices are effective and safe, long-acting reversible contraceptives, but the risk of uterine perforation occurs with an estimated incidence of 1 to 2 per 1000 insertions. The European Active Surveillance Study for Intrauterine Devices, a European prospective observational study…
Timing of Antiretroviral Therapy Initiation and Risk of Cancer among Persons Living with HIV
Persons living with human immunodeficiency virus (HIV; PLWH) experience a high burden of cancer. It remains unknown which cancer types are reduced in PLWH with earlier initiation of antiretroviral therapy (ART). We evaluated AIDS-free, ART-naive PLWH during 1996-2014 from 22…
Particulate Air Pollution and Risk of Cardiovascular Events Among Adults With a History of Stroke or Acute Myocardial Infarction
Background Previous studies have found associations between fine particulate matter
The Association of Lactation Duration with Visceral and Pericardial Fat Volumes in Parous Women: the CARDIA Study
Lactation is associated with lower risks for cardiovascular disease in women. Organ-related adiposity, which plays significant roles in the development of cardiometabolic diseases, could help explain this observation. We evaluated the association of lactation duration with visceral (VAT) and pericardial…
Ten-Year Follow-up of Persons With Sun-Damaged Skin Associated With Subsequent Development of Cutaneous Squamous Cell Carcinoma
Risk of cutaneous squamous cell carcinoma (cSCC) after the diagnosis of actinic keratosis (AK) has not been studied during long follow-up periods. To estimate the risk up to 10 years and identify risk factors for cSCC development. This longitudinal cohort…
Intraocular Pressure Reduction After Phacoemulsification: A Matched Cohort Study
Phacoemulsification has been linked to lowered intraocular pressure (IOP) in patients with glaucoma, ocular hypertension, anatomic narrow angles, and in glaucoma suspects, but the magnitude of change has varied. Retrospective cohort study. Patients with glaucoma treated from June 2010 through…
Comparison of dementia risk after age 50 between individuals with and without HIV infection
To compare risk of dementia after age 50 by HIV status among individuals in a primary care setting. Observational cohort study; participants were identified from 2013 to 2017 and followed through 2019. Participants were people with HIV (PWH) on antiretroviral…
Patterns and Factors Associated With Adherence to Lung Cancer Screening in Diverse Practice Settings
For lung cancer screening to confer mortality benefit, adherence to annual screening with low-dose computed tomography scans is essential. Although the National Lung Screening Trial had an adherence rate of 95%, current data are limited on screening adherence across diverse…
Clustering of Social and Physical Pain Variables and Their Association With Mortality in Two Population-Based Cohorts
Social pain and physical pain are related bidirectionally, but how these variables cluster in the population is unknown. This study included 2833 women from the Study of Women's Health Across the Nation (SWAN), a community-based cohort of middle-aged women, and…
Dual trajectories of physical activity and blood lipids in midlife women: The Study of Women’s Health Across the Nation
Physical activity (PA) has the potential to attenuate cardiovascular disease risk in midlife women through multiple pathways, including improving lipid profiles. Longitudinal patterns of PA and blood lipid levels have not been studied in midlife women. Our study identified trajectories…
mHealth Mindfulness Intervention for Women with Moderate-to-Moderately-Severe Antenatal Depressive Symptoms: a Pilot Study Within an Integrated Health Care System
Traditional mindfulness-based interventions have been shown to reduce depression symptoms in pregnant women, although in-person classes may pose significant accessibility barriers, particularly during the COVID-19 pandemic. Mobile technology offers greater convenience, but little is known regarding the efficacy of self-paced,…
A Risk Score to Predict Clostridioides difficile Infection
Clostridioides difficile infection (CDI) is a major cause of severe diarrhea. In this retrospective study, we identified CDI risk factors by comparing demographic and clinical characteristics for Kaiser Permanente Northern California members ≥18 years old with and without laboratory-confirmed incident…
Gestational weight gain and adverse pregnancy outcomes by pre-pregnancy BMI category in women with chronic hypertension: A cohort study
It is important to understand relationships of gestational weight gain with adverse pregnancy outcomes in women with chronic hypertension, given their high baseline risk of adverse outcomes. We assessed associations of gestational weight gain with adverse pregnancy outcomes in women…
Metalworking Fluids and Colon Cancer Risk: Longitudinal Targeted Minimum Loss-based Estimation
Metalworking fluids (MWFs) are a class of complex mixtures of chemicals and oils, including several known carcinogens that may pose a cancer hazard to millions of workers. Reports on the relation between MWFs and incident colon cancer have been mixed.…
Cross-cancer evaluation of polygenic risk scores for 16 cancer types in two large cohorts
Even distinct cancer types share biological hallmarks. Here, we investigate polygenic risk score (PRS)-specific pleiotropy across 16 cancers in European ancestry individuals from the Genetic Epidemiology Research on Adult Health and Aging cohort (16,012 cases, 50,552 controls) and UK Biobank…
Development and Implementation of Evidence-based Risk Stratification Tools for Diabetic Retinopathy Screening and Population Management
This project aims to develop and implement evidence-based risk stratification tools for diabetic retinopathy screening and population management.
The relationship of smoking and unhealthy alcohol use to the HIV care continuum among people with HIV in an integrated health care system
Smoking tobacco and unhealthy alcohol use may negatively influence HIV care continuum outcomes but have not been examined in combination. Participants were people with HIV (PWH) in Kaiser Permanente Northern California. Predictors included smoking status and unhealthy alcohol use (exceeding…
Recruitment strategies and design considerations in a trial of resistance training to prevent dose-limiting toxicities in colon cancer patients undergoing chemotherapy
Low muscle is associated with an increased risk of chemotherapy-related dose limiting toxicities (DLT) in cancer patients. Resistance training (RT) improves muscle mass; however, the effects of RT on preventing DLTs and dose reductions in colon cancer patients has not…
Exercise During the First Trimester of Pregnancy and the Risks of Abnormal Screening and Gestational Diabetes Mellitus
To estimate the effects of exercise during the first trimester on the risks of abnormal screening and gestational diabetes mellitus (GDM). Data come from PETALS, a prospectively followed pregnancy cohort (n = 2,246, 79% minorities) receiving care at Kaiser Permanente…
PREDICTION OF OBSTETRIC AND FETAL COMPLICATIONS USING AUTOMATED ELECTRONIC HEALTH RECORD DATA
An increasing number of delivering women experience major morbidity and mortality. Limited work has been done on automated predictive models that could be used for prevention. Using only routinely collected obstetrical data, this study aimed to develop a predictive model…
Fitting a shared frailty illness-death model to left-truncated semi-competing risks data to examine the impact of education level on incident dementia
Semi-competing risks arise when interest lies in the time-to-event for some non-terminal event, the observation of which is subject to some terminal event. One approach to assessing the impact of covariates on semi-competing risks data is through the illness-death model…
Long-Term PM2.5 Exposure and Risks of Ischemic Heart Disease and Stroke Events: Review and Meta-Analysis
Background Fine particulate matter
Incidence and predictors of type 1 diabetes among younger adults aged 20-45 years: The diabetes in young adults (DiYA) study
To estimate incidence of type 1 diabetes (T1D) and to develop a T1D prediction model among young adults. Adults 20-45 years newly-diagnosed with diabetes in 2017 were identified within Kaiser Permanente's healthcare systems in California and invited for diabetes autoantibody (DAA)…
A Randomized Encouragement Trial to Increase Mail Order Pharmacy Use and Medication Adherence in Patients with Diabetes
Mail order pharmacy (MOP) use has been linked to improved medication adherence and health outcomes among patients with diabetes. However, no large-scale intervention studies have assessed the effect of encouraging MOP use on medication adherence. To assess an intervention to…
Maternal immune response and air pollution exposure during pregnancy: insights from the Early Markers for Autism (EMA) study
Perinatal exposure to air pollution and immune system dysregulation are two factors consistently associated with autism spectrum disorders (ASD) and other neurodevelopmental outcomes. However, little is known about how air pollution may influence maternal immune function during pregnancy. To assess…
Risk of complete atypical femur fracture with Oral bisphosphonate exposure beyond three years
Bisphosphonate (BP) therapy has been associated with atypical femur fracture (AFF). However, the threshold of treatment duration leading to increased AFF risk is unclear. In a retrospective cohort of older women initiating BP, we compared the AFF risk associated with…
Development and Validation of Machine Learning Models: Electronic Health Record Data To Predict Visual Acuity After Cataract Surgery
To develop predictive models of final corrected distance visual acuity (CDVA) following cataract surgery using machine learning algorithms and electronic health record data. In this predictive modeling study we used decision tree, random forest, and gradient boosting. We included the…
Validation Study of Kaiser Permanente Bedside Dysphagia Screening Tool in Acute Stroke Patients
Dysphagia occurs in up to 50% of patients with acute stroke symptoms, resulting in increased aspiration pneumonia rates and mortality. The purpose of this study was to validate a health system's dysphagia (swallow) screening tool used since 2007 on all…
Bisphosphonate Treatment Beyond 5 Years and Hip Fracture Risk in Older Women
Clinical trials have demonstrated the antifracture efficacy of bisphosphonate drugs for the first 3 to 5 years of therapy. However, the efficacy of continuing bisphosphonate for as long as 10 years is uncertain. To examine the association of discontinuing bisphosphonate…
Associations between spousal caregiving and health among older adults in Mexico: A targeted estimation approach
To evaluate associations between spousal caregiving and mental and physical health among older adults in Mexico. Data come from the Mexican Health & Aging Study, a national population-based study of adults ≥50 years and their spouses (2001-2015). We compared outcomes…
Health System-Based Unhealthy Alcohol Use Screening and Treatment Comparing Demographically-Matched Participants With and Without HIV
Unhealthy alcohol use among persons living with HIV (PLWH) is linked to significant morbidity, and use of alcohol services may differ by HIV status. Our objective was to compare unhealthy alcohol use screening and treatment by HIV status in primary…
Association of Valproic Acid Use, a Potent Histone Deacetylase Inhibitor, and Melanoma Risk
Histone deacetylase inhibitors, including valproic acid, selectively induce cellular differentiation and apoptosis in melanoma cells. No published pharmacoepidemiologic studies have explored the association between valproic acid use and melanoma risk. We conducted a retrospective cohort study of adult white Kaiser…
Identifying Ectopic Pregnancy in a Large Integrated Health Care Delivery System: Algorithm Validation
Surveillance of ectopic pregnancy (EP) using electronic databases is important. To our knowledge, no published study has assessed the validity of EP case ascertainment using electronic health records. We aimed to assess the validity of an enhanced version of a…
A Mobile Health Mindfulness Intervention for Women With Moderate to Moderately Severe Postpartum Depressive Symptoms: Feasibility Study
Approximately 20% of women suffer from postpartum depression (PPD). Due to barriers such as limited access to care, half of the women with PPD do not receive treatment. Therefore, it is critical to identify effective and scalable interventions. Traditional mindfulness…
Individual and Neighborhood Factors Associated with Failure to Vaccinate against Influenza during Pregnancy
Uptake of influenza vaccine among pregnant women remains low. We investigated whether unvaccinated pregnant women were clustered geographically and determined factors associated with failure to vaccinate using spatial and multivariate logistic regression analyses. Pregnant women who were members of Kaiser…
Presentation of Rash in a Community-Based Health System
Coordination of care between primary care providers and dermatologists is important to ensure high quality and cost efficiency. In our integrated care setting, we used a retrospective cohort study to assess which patients self-refer to dermatology and which returned for…
Changing Provider PSA Screening Behavior Using Best Practice Advisories: Interventional Study in a Multispecialty Group Practice
Most guidelines recommend against PSA-based screening for prostate cancer in men ≥ 70 years of age. Adherence to these guidelines is variable. To determine whether the use of a "Best Practice Advisory" (BPA) intervention within the electronic medical record (EMR)…
Bone Mineral Density in Older U.S. Filipino, Chinese, Japanese, and White Women
Bone mineral density (BMD) reference data exist for U.S. White, Black, and Hispanic (Mexican American) populations but not for U.S. Asians. Few studies have compared BMD findings among different U.S. Asian ethnicities. Retrospective observational study. Large northern California healthcare system.…
Consequences of depletion of susceptibles for hazard ratio estimators based on propensity scores
We use simulated data to examine the consequences of depletion of susceptibles for hazard ratio (HR) estimators based on a propensity score (PS). First, we show that the depletion of susceptibles attenuates marginal HRs toward the null by amounts that…
Early Screening of African Americans (45-50 Years Old) in a Fecal Immunochemical Test-based Colorectal Cancer Screening Program
Some guidelines recommend starting colorectal cancer (CRC) screening before age 50 years for African Americans, but there are few data on screening uptake and yield in this population. We performed a prospective study of fecal immunochemical test (FIT) screening among…
Prospective development of a prostate cancer risk calculator in a racially diverse population: The Kaiser Permanente Prostate Cancer Risk Calculator
To prospectively develop a prostate cancer (CaP) risk calculator in a racially diverse population. All patients referred for prostate biopsy due to an elevated prostate-specific antigen or abnormal digital rectal exam in a 19-months period at Kaiser Permanente Northern California…
Standardized reporting and management of suspicious findings on chest computed tomography is associated with improved lung cancer diagnosis in an observational study
Follow-up of chest CT scan findings suspicious for lung cancer may be delayed because of inadequate documentation. Standardized reporting and follow-up may reduce time to diagnosis and care for lung cancer. We implemented a reporting system that standardizes tagging of…
Early life household intactness and timing of pubertal onset in girls: a prospective cohort study
Girls who experience early-life familial stress may have heightened risk of early puberty, which has adverse implications for adolescent and adult health. We assessed the association between household intactness and pubertal onset using a racially/ethnically diverse cohort of girls from…
Identification of 31 loci for mammographic density phenotypes and their associations with breast cancer risk
Mammographic density (MD) phenotypes are strongly associated with breast cancer risk and highly heritable. In this GWAS meta-analysis of 24,192 women, we identify 31 MD loci at P
Inpatient-outpatient shared electronic health records: telemedicine and laboratory follow-up after hospital discharge
Continuity of patient information across settings can improve transitions after hospital discharge, but outpatient clinicians often have limited access to complete information from recent hospitalizations. We examined whether providers' timely access to clinical information through shared inpatient-outpatient electronic health records…
Gestational weight gain, birthweight and early-childhood obesity: between- and within-family comparisons
Associations of excessive gestational weight gain (GWG) with greater birthweight and childhood obesity may be confounded by shared familial environment or genetics. Sibling comparisons can minimize variation in these confounders because siblings grow up in similar environments and share the…
Association of Low Muscle Mass and Low Muscle Radiodensity With Morbidity and Mortality for Colon Cancer Surgery
Given the risks of postoperative morbidity and its consequent economic burden and impairment to patients undergoing colon resection, evaluating risk factors associated with complications will allow risk stratification and the targeting of supportive interventions. Evaluation of muscle characteristics is an…
Determining Which of Several Simultaneously Administered Vaccines Increase Risk of an Adverse Event
Childhood immunization schedules often involve multiple vaccinations per visit. When increased risk of an adverse event is observed after simultaneous (same-day) vaccinations, it can be difficult to ascertain which triggered the adverse event. This methods paper discusses a systematic process…
Feasibility of Measuring Preferences for Chemotherapy Among Early-Stage Breast Cancer Survivors Using a Direct Rank Ordering Multicriteria Decision Analysis Versus a Time Trade-Off
Chemotherapy is increasingly a preference-based choice among women diagnosed with early-stage breast cancer. Multicriteria decision analysis (MCDA) is a promising but underutilized method to facilitate shared decision making. We explored the feasibility of conducting an MCDA using direct rank ordering…
History of Early Childhood Infections and Acute Lymphoblastic Leukemia Risk Among Children in a U.S. Integrated Health Care System
Surrogate measures of infectious exposures have been consistently associated with lower childhood acute lymphoblastic leukemia (ALL) risk. However, recent reports have suggested that physician-diagnosed early-life infections increase ALL risk, thereby raising the possibility that stronger responses to infections might promote…
Pilot pragmatic randomized trial of mHealth mindfulness-based intervention for advanced cancer patients and their informal caregivers
Assess the feasibility of conducting a cluster randomized trial (RCT) comparing technology-delivered mindfulness-based intervention (MBI) programs against a waitlist control arm targeting advanced cancer patients and their informal caregivers. Two-arm cluster RCT within Kaiser Permanente Northern California (KPNC). We recruited…
Pan-cancer study detects genetic risk variants and shared genetic basis in two large cohorts
Deciphering the shared genetic basis of distinct cancers has the potential to elucidate carcinogenic mechanisms and inform broadly applicable risk assessment efforts. Here, we undertake genome-wide association studies (GWAS) and comprehensive evaluations of heritability and pleiotropy across 18 cancer types…
Trends and correlates of self-reported alcohol and nicotine use among women before and during pregnancy, 2009-2017
To examine trends and correlates of frequency of self-reported alcohol and nicotine use among pregnant women. Cross-sectional study of 363,240 pregnancies from 2009 to 2017 screened for self-reported substance use at their first prenatal visit in Kaiser Permanente Northern California.…
Variation in physician-directed immunohistochemistry screening among women with endometrial cancer
Immunohistochemistry screening is a reliable method for identifying women with endometrial cancer who are at risk for Lynch syndrome, but clinical workflows used to implement immunohistochemistry screening protocols can vary by institution. The goal of this study was to investigate…
Evaluation of a Vaccine-Communication Tool for Physicians
To evaluate a Kaiser Permanente Northern California physician training tool entitled "Effective Communication without Confrontation" aimed at improving communication with vaccine-hesitant parents, building trust, and alleviating physician stress surrounding vaccination visits. Trainings were held May to July 2015. Pre- and…
Smoking and cessation treatment among persons with and without HIV in a U.S. integrated health system
Persons with HIV (PWH) are more likely to smoke and are more susceptible to the harmful effects of smoking than persons without HIV. We examined smoking patterns and use of cessation treatment among PWH and persons without HIV in a…
Increased Risk of Colorectal Cancer in Individuals With a History of Serrated Polyps
Serrated polyp (SPs) are precursors to 20% to 30% of cases of colorectal tumors, but patients' long-term risk after removal of SPs is poorly understood. We investigated the risk of colorectal cancer (CRC) in individuals with a history of SPs.…
Leveraging Machine Learning to Improve Risk Prediction for Chemotherapy Induced Neuropathy
Chemotherapy-associated peripheral neuropathy (CPN) affects nearly 70% of cancer patients. An estimated 30% of cancer survivors have persistent CPN, which can have a devastating impact on their quality of life and functioning. Our objective is to develop and validate a…
Comparison of two Lynch screening strategies in endometrial cancer in a California health system
Compare detection of Lynch syndrome in endometrial cancer between regions of a health care system with different screening strategies. A retrospective study of endometrial cancer (EC) cases from 2 regions of an integrated health care system (Kaiser Permanente Northern (KPNC)…
Cesarean Delivery and the Risk of Atopic Dermatitis in Children
Caesarean delivery (C-section) may disrupt maternal-infant microbial transfer and alter immune system development and subsequent risk for atopic dermatitis. Investigate the association between C-section and atopic dermatitis by age four and examine potential sources of bias in the relationship in…
Comparison of Overall and Comorbidity-Free Life Expectancy Between Insured Adults With and Without HIV Infection, 2000-2016
Antiretroviral therapy (ART) has improved life expectancy for individuals with HIV infection, but recent data comparing life span and comorbidity-free years by HIV status are lacking. To quantify the gap in life span and comorbidity-free years by HIV status among…
Association of Azithromycin Use With Cardiovascular Mortality
Azithromycin is one of the most commonly prescribed antibiotics in the US. It has been associated with an increased risk of cardiovascular death in some observational studies. To estimate the relative and absolute risks of cardiovascular and sudden cardiac death…
Patient Characteristics Associated With Choosing a Telemedicine Visit vs Office Visit With the Same Primary Care Clinicians
Video or telephone telemedicine can offer patients access to a clinician without arranging for transportation or spending time in a waiting room, but little is known about patient characteristics associated with choosing between telemedicine or office visits. To examine patient…
A telehealth lifestyle intervention to reduce excess gestational weight gain in pregnant women with overweight or obesity (GLOW): a randomised, parallel-group, controlled trial
Excess gestational weight gain (GWG) among women with overweight or obesity synergistically increases their already elevated risk of having gestational diabetes, a caesarean delivery, a large for gestational age infant, and post-partum weight retention, and increases their child's risk of…
Prenatal Depression and Diet Quality During Pregnancy
Maternal nutrition during pregnancy has a significant effect on the health of the offspring and mother, highlighting the need for identifying factors that may affect diet during pregnancy. Research in nonpregnant and pregnant populations suggest depression may play a role.…
Time-to-event analysis when the event is defined on a finite time interval
Acute graft-versus-host disease (GVHD) is a frequent complication following hematopoietic cell transplantation (HCT). Research on risk factors for acute GVHD has tended to ignore two important clinical issues. First, post-transplant mortality is high. In our motivating data, 100-day post-HCT mortality…
Inverse probability weighted Cox model in multi-site studies without sharing individual-level data
The inverse probability weighted Cox proportional hazards model can be used to estimate the marginal hazard ratio. In multi-site studies, it may be infeasible to pool individual-level datasets due to privacy and other considerations. We propose three methods for making…
Comparative Effectiveness of 2 Diabetes Prevention Lifestyle Programs in the Workplace: The City and County of San Francisco Diabetes Prevention Trial
Data on the comparative effectiveness of Diabetes Prevention Programs (DPPs) in the workplace are limited. Between September 2015 and July 2016, employees of the City and County of San Francisco who were at risk for type 2 diabetes (N =…
Additive effects of blood donor smoking and gamma irradiation on outcome measures of red blood cell transfusion
Recent publications have reported conflicting results regarding the role of blood donor tobacco use on hemoglobin (Hb) levels in patients after red blood cell (RBC) transfusion. We examined associations and interactions between donor, component, and recipient factors to better understand…
Proton Pump Inhibitor Use and Risk of Gastric, Colorectal, Liver, and Pancreatic Cancers in a Community-Based Population
Proton pump inhibitors (PPIs) are commonly used for gastrointestinal disorders; given they increase the systemic levels of gastrin, a trophic hormone, there is a concern about their carcinogenicity. This study evaluated the association between PPI use and gastrointestinal cancers. We…
Initial Glycemic Control and Care Among Younger Adults Diagnosed With Type 2 Diabetes
The prevalence of type 2 diabetes is increasing among adults under age 45. Onset of type 2 diabetes at a younger age increases an individual's risk for diabetes-related complications. Given the lasting benefits conferred by early glycemic control, we compared…
Alcohol and tobacco use in relation to mammographic density in 23,456 women
Percent density (PD) is a strong risk factor for breast cancer that is potentially modifiable by lifestyle factors. PD is a composite of the dense (DA) and nondense (NDA) areas of a mammogram, representing predominantly fibroglandular or fatty tissues, respectively.…
Prediction of Occult Uterine Sarcoma prior to Hysterectomy for Women with Leiomyoma or Abnormal Bleeding
To develop a risk prediction model for occult uterine sarcoma using preoperative clinical characteristics in women undergoing hysterectomy for presumed uterine leiomyomata. Cases of uterine sarcoma were identified from the electronic medical records. Age/race-matched controls were selected at a 2:1…
Exploiting nonsystematic covariate monitoring to broaden the scope of evidence about the causal effects of adaptive treatment strategies
In studies based on electronic health records (EHR), the frequency of covariate monitoring can vary by covariate type, across patients, and over time, which can limit the generalizability of inferences about the effects of adaptive treatment strategies. In addition, monitoring…
Cumulative Adherence to Secondary Prevention Guidelines and Mortality After Acute Myocardial Infarction
Background The survival benefit associated with cumulative adherence to multiple clinical and lifestyle-related guideline recommendations for secondary prevention after acute myocardial infarction (AMI) is not well established. Methods and Results We examined adults with AMI (mean age 68 years; 64% men)…
Depletion of Susceptibles Bias in Analyses of Intra-season Waning of Influenza Vaccine Effectiveness
Bias arises in studies of waning vaccine effectiveness when higher-risk individuals are depleted from the at-risk population at different rates between study groups. We examined how this bias arises and how to avoid it. A reanalysis of data from California…
Association of immunosuppression and HIV viremia with anal cancer risk in persons living with HIV in the United States and Canada
People living with human immunodeficiency virus (HIV; PLWH) have a markedly elevated anal cancer risk, largely due to loss of immunoregulatory control of oncogenic human papillomavirus infection. To better understand anal cancer development and prevention, we determined whether recent, past,…
Long-term Risk of Colorectal Cancer and Related Death After Adenoma Removal in a Large, Community-based Population
The long-term risks of colorectal cancer (CRC) and CRC-related death following adenoma removal are uncertain. Data are needed to inform evidence-based surveillance guidelines, which vary in follow-up recommendations for some polyp types. Using data from a large, community-based integrated health…
Risk of Mortality between Untreated and Treated Papillary Thyroid Cancer: A Matched Cohort Analysis
To examine the association between treatment status and mortality risk among patients with papillary thyroid cancer (PTC). We identified 3,679 adults with PTC. Thirty-one untreated patients were matched to 155 treated patients. Hazards ratios (HR) and 95% confidence intervals (CIs)…
Exercise During the First Trimester and Infant Size at Birth: Targeted Maximum Likelihood Estimation of the Causal Risk Difference
This cohort study sought to estimate the differences in risk of delivering infants who were small or large for gestational age (SGA or LGA, respectively) according to exercise during the first trimester of pregnancy (vs. no exercise) among 2,286 women…
Learning to learn from data: Using deep adversarial learning to construct optimal statistical procedures
Traditionally, statistical procedures have been derived via analytic calculations whose validity often relies on sample size growing to infinity. We use tools from deep learning to develop a new approach, adversarial Monte Carlo meta-learning, for constructing optimal statistical procedures. Statistical…
Association of Mobile Patient Portal Access With Diabetes Medication Adherence and Glycemic Levels Among Adults With Diabetes
Online patient portals support self-management, and mobile devices expand portal access, but whether this translates to improvements in diabetes outcomes is unclear. To examine the association of adding mobile patient portal access with diabetes medication adherence and glycemic levels among…
Life Expectancy of Insured People With and Without Hepatitis C Virus Infection, 2007-2017
Among 25 291 and 4 921 830 people with and without hepatitis C, life expectancy at age 20 increased 1.8 years and 0.3 years from the interferon to interferon-free era, respectively. Increases were highest for racial and/or ethnic minority groups…
Determinants of Oral Bisphosphonate Use Beyond 5 Years
Few studies have examined factors that determine bisphosphonate (BP) continuation beyond 5 years in clinical practice. To investigate factors associated with BP continuation among women who completed 5 years of BP therapy. Women who received 5 consecutive years of oral…
Adjuvant endocrine therapy for breast cancer patients: impact of a health system outreach program to improve adherence
Reports suggest that up to 50% of women with hormone receptor-positive (HR+) breast cancer (BC) do not complete the recommended 5 years of adjuvant endocrine therapy (AET). We examined the impact of an outreach program at Kaiser Permanente Northern California (KPNC)…
Body Composition, Adherence to Anthracycline and Taxane-Based Chemotherapy, and Survival After Nonmetastatic Breast Cancer
Although most chemotherapies are dosed on body surface area or weight, body composition (ie, the amount and distribution of muscle and adipose tissues) is thought to be associated with chemotherapy tolerance and adherence. To evaluate whether body composition is associated…
Comparison of Mortality and Major Cardiovascular Events Among Adults With Type 2 Diabetes Using Human vs Analogue Insulins
The comparative cardiovascular safety of analogue and human insulins in adults with type 2 diabetes who initiate insulin therapy in usual care settings has not been carefully evaluated using machine learning and other rigorous analytic methods. To examine the association…
Vaccine effectiveness of cell-culture relative to egg-based inactivated influenza vaccine during the 2017-18 influenza season
There is concern that influenza vaccine effectiveness (VE) may be attenuated by passage in eggs during manufacture. We compared quadrivalent cell-culture vaccine with egg-based vaccines, most of which were trivalent, against influenza A and B during 2017-2018 when A(H3N2) and…
Identifying hypertension in pregnancy using electronic medical records: The importance of blood pressure values
To incorporate blood pressure (BP), diagnoses codes, and medication fills from electronic medical records (EMR) to identify pregnant women with hypertension. A retrospective cohort study of singleton pregnancies at three US integrated health delivery systems during 2005-2014. Women were considered…
Use of Time-Dependent Propensity Scores to Adjust Hazard Ratio Estimates in Cohort Studies with Differential Depletion of Susceptibles
Estimating hazard ratios (HR) presents challenges for propensity score (PS)-based analyses of cohorts with differential depletion of susceptibles. When the treatment effect is not null, cohorts that were balanced at baseline tend to become unbalanced on baseline characteristics over time…
Outcomes of Robotic Hysterectomy for Treatment of Benign Conditions: Influence of Patient Complexity
Robotic hysterectomy may offer advantages for complex cases over the conventional laparoscopic approach. To assess the association of surgical approach (robotic vs conventional) with blood loss, risks of readmission, reoperation, complications, and average operative time. In a retrospective cohort study,…
Changes in Prostate Cancer Presentation Following the 2012 USPSTF Screening Statement: Observational Study in a Multispecialty Group Practice
In 2012, the US Preventive Services Task Force (USPSTF) recommended against PSA-based screening for prostate cancer in men of all ages. Following this change, screening declined yet the complete impact on clinical presentation is not well defined in the screen-eligible…
Effect of Sex, Age and Positivity Threshold on Fecal Immunochemical Test Accuracy: a Systematic Review and Meta-Analysis
Quantitative fecal immunochemical tests (FITs) for hemoglobin are commonly used for colorectal cancer (CRC) screening. We aimed to quantify the change in CRC and advanced adenoma detection and number of positive test results at different positivity thresholds and by sex…
A primer on quantitative bias analysis with positive predictive values in research using electronic health data
In health informatics, there have been concerns with reuse of electronic health data for research, including potential bias from incorrect or incomplete outcome ascertainment. In this tutorial, we provide a concise review of predictive value-based quantitative bias analysis (QBA), which…
Risk Estimates for Diabetes and Hypertension with Different Physical Activity Methods
To estimate risks of incident type 2 diabetes (T2D) and stage 2 and greater hypertension associated with self-reported and accelerometer-determined moderate-vigorous physical activity (MVPA) separately and adjusted for each other. The sample included 2291 black and white men and women,…
Depletion-of-susceptibles bias in influenza vaccine waning studies: how to ensure robust results
Vaccine effectiveness studies are subject to biases due to depletion-of-persons at risk of infection, or at especially high risk of infection, at different rates from different groups (depletion-of-susceptibles bias), a problem that can also lead to biased estimates of waning…
Haloperidol and Prostate Cancer Prevention: More Epidemiologic Research Needed
The antipsychotic drug haloperidol has antiproliferative and growth-inhibiting properties on prostate cancer cell lines in vitro by binding the sigma 1 protein. Evidence is needed regarding a possible preventive association in men. To examine whether our epidemiologic data support an…
Validity of Self-reported Cannabis Use Among Pregnant Females in Northern California
Most clinical and epidemiologic estimates of prenatal cannabis use are based on self-report, and the validity of self-reported cannabis use has not been examined in a large, representative population of pregnant women. We determined the validity of self-reported prenatal cannabis…
Association of donor age, body mass index, hemoglobin, and smoking status with in-hospital mortality and length of stay among red blood cell-transfused recipients
Recent publications have reported conflicting findings regarding associations of blood donor demographics and mortality of transfused patients. We hypothesized that the analysis of additional donor characteristics and consideration of alternative outcomes might provide insight into these disparate results. We analyzed…
Comparative Effectiveness Study of Face-to-Face and Teledermatology Workflows for Diagnosing Skin Cancer
The effectiveness and value of teledermatology and face-to-face workflows for diagnosing lesions are not adequately understood. We compared the risks of biopsy and cancer diagnosis among 2 face-to-face workflows (direct referral and roving dermatologist) and 4 teledermatology workflows. Retrospective study…
Adipose Tissue Distribution and Cardiovascular Disease Risk Among Breast Cancer Survivors
Cardiovascular disease (CVD) is a major source of morbidity and mortality among breast cancer survivors. Although body mass index (BMI) is associated with CVD risk, adipose tissue distribution may better identify patients with a high risk of CVD after breast…
Use of electronic health record data and machine learning to identify candidates for HIV pre-exposure prophylaxis: a modelling study
The limitations of existing HIV risk prediction tools are a barrier to implementation of pre-exposure prophylaxis (PrEP). We developed and validated an HIV prediction model to identify potential PrEP candidates in a large health-care system. Our study population was HIV-uninfected…
Effect of donor, component and recipient characteristics on hemoglobin increments following red blood cell transfusion
Significant research has focused individually on blood donors, product preparation and storage, and optimal transfusion practice. To better understand the interplay between these factors on measures of red blood cell (RBC) transfusion efficacy, we conducted a linked analysis of blood…
Enhanced Recovery After Surgery to Change Process Measures and Reduce Opioid Use After Cesarean Delivery: A Quality Improvement Initiative
To evaluate implementation of an enhanced recovery after surgery (ERAS) program for patients undergoing elective cesarean delivery by comparing opioid exposure, multimodal analgesia use, and other process and outcome measures before and after implementation. An ERAS program was implemented among…
Depot Medroxyprogesterone Acetate, Oral Contraceptive, Intrauterine Device Use, and Fracture Risk
To assess fracture risk among women with depot medroxyprogesterone acetate (DMPA), oral contraceptive pill (OCP), and intrauterine device (IUD) use. A retrospective cohort study of 308,876 women age 12-45 years who initiated DMPA, combined or progestin-only OCPs, and copper and…
Pre- and Early Pregnancy Onset Depression and Subsequent Rate of Gestational Weight Gain
Background:Depression is associated with weight change outside of pregnancy. We assessed associations of prepregnancy or early pregnancy onset depression with gestational weight gain (GWG) rate overall and according to Institute of Medicine (IOM) recommendations. Materials and Methods:Depression from 6 months…
Long-term effectiveness of zoster vaccine live for postherpetic neuralgia prevention
Postherpetic neuralgia (PHN) occurs in 5-30% of individuals with herpes zoster (HZ) and is characterized by long-lasting pain. Zoster vaccine live (ZVL) is licensed for people 50 years and older to prevent HZ and PHN. This study evaluated vaccine effectiveness…
Breastfeeding and timing of pubertal onset in girls: a multiethnic population-based prospective cohort study
Early puberty is associated with higher risk of adverse health and behavioral outcomes throughout adolescence and adulthood. US girls are experiencing earlier puberty with substantial racial/ethnic differences. We examined the association between breastfeeding and pubertal timing to identify modifiable risk…
Targeted learning with daily EHR data
Electronic health records (EHR) data provide a cost- and time-effective opportunity to conduct cohort studies of the effects of multiple time-point interventions in the diverse patient population found in real-world clinical settings. Because the computational cost of analyzing EHR data…
Self-reported Daily, Weekly, and Monthly Cannabis Use Among Women Before and During Pregnancy
As the overall prevalence of prenatal cannabis use rises, it is vital to also monitor trends in the frequency of cannabis use in the period leading up to and during pregnancy because more frequent use may confer greater health risks…
Acellular Pertussis Vaccine Effectiveness Over Time
To determine pertussis risk by diphtheria-tetanus-acellular pertussis (DTaP) vaccination status and time since last DTaP dose. Children born at Kaiser Permanente Northern California between 1999 and 2016 were followed from 3 months of age until they tested positive for pertussis;…
Colorectal Cancer Screening in People With and Without HIV in an Integrated Health Care Setting
As people with HIV (PWH) live longer, age-appropriate colorectal cancer (CRC) screening is increasingly important. Limited data exist on CRC screening and outcomes comparing PWH and persons without HIV. Large integrated health care system. This study included PWH and demographically…
Stressors in Midlife and Risk of Dementia: The Role of Race and Education
Posttraumatic stress disorder is associated with increased dementia risk but less is known about stress because of everyday problems in diverse populations. A total of 9605 health care plan members who provided information regarding midlife stressors in 1972 to 1973…
A Randomized Study of Values Affirmation to Promote Interest in Diabetes Prevention Among Women With a History of Gestational Diabetes
The objective of this study was to test whether 2 interventions promote interest in diabetes prevention among women with a history of gestational diabetes mellitus, who face high lifetime risk for diabetes. We designed an email outreach message promoting an…
Association of Blood Donor Sex and Prior Pregnancy With Mortality Among Red Blood Cell Transfusion Recipients
Evidence regarding associations of blood donor sex with mortality among red blood cell transfusion recipients is conflicting. To study associations of donor sex and prior pregnancy with mortality of transfusion recipients. Data from 3 retrospective cohorts of transfusion recipients (the…
Telomere length and socioeconomic status at neighborhood and individual levels among 80,000 adults in the Genetic Epidemiology Research on Adult Health and Aging cohort
Telomere length (TL) may serve as a biologic marker of aging. We examined neighborhood and individual-level socioeconomic status (SES) in relation to TL. The study included 84,996 non-Hispanic white subjects from the Genetic Epidemiology Research on Adult Health and Aging…
Reproductive Factors and Mammographic Density: Associations Among 24,840 Women and Comparison of Studies Using Digitized Film-Screen Mammography and Full-Field Digital Mammography
Breast density is a modifiable factor that is strongly associated with breast cancer risk. We sought to understand the influence of newer technologies of full-field digital mammography (FFDM) on breast density research and to determine whether results are comparable across…
SemiCompRisks: An R Package for the Analysis of Independent and Cluster-correlated Semi-competing Risks Data
Semi-competing risks refer to the setting where primary scientific interest lies in estimation and inference with respect to a non-terminal event, the occurrence of which is subject to a terminal event. In this paper, we present the R package SemiCompRisks…
Using Pharmacy Data and Adherence to Define Long-Term Bisphosphonate Exposure in Women
Assigning drug exposure is a necessary first step in examining bisphosphonate (BP) treatment in observational studies using pharmacy data. To determine whether the choice of adherence level using the proportion of days covered (PDC) affected BP exposure assignment. 10,381 female…
Adipose Tissue Distribution and Survival Among Women with Nonmetastatic Breast Cancer
Previous studies of breast cancer survival have not considered specific depots of adipose tissue such as subcutaneous adipose tissue (SAT) and visceral adipose tissue (VAT). This study assessed these relationships among 3,235 women with stage II and III breast cancer…
Prompting Patients with Poorly Controlled Diabetes to Identify Visit Priorities Before Primary Care Visits: a Pragmatic Cluster Randomized Trial
Most patients with diabetes do not meet all evidence-based goals of care, and many patients report poor communication and lack of involvement in decision-making during primary care visits. To test the hypothesis that a "Pre-Visit Prioritization" secure email message could…
Evaluation of Complex Interventions on Drug (Re)Fill Behavior Using Electronic Health Care Data
This study develops generalized per-protocol analyses based on Inverse Probability Weighting and Targeted Learning to control for or evaluate the effect of medication nonadherence in observational studies that use electronic health databases to inform the management of chronic conditions. Unlike…
Hepatitis C treatment uptake and response among human immunodeficiency virus/hepatitis C virus-coinfected patients in a large integrated healthcare system.
U.S. guidelines recommend that patients coinfected with human immunodeficiency virus (HIV) and hepatitis C virus (HCV) be prioritized for HCV treatment with direct-acting antiviral agents (DAAs), but the high cost of DAAs may contribute to disparities in treatment uptake and…
Intra-season Waning of Influenza Vaccine Effectiveness
In the United States, it is recommended that healthcare providers offer influenza vaccination by October, if possible. However, if the vaccine's effectiveness soon begins to wane, the optimal time for vaccination may be somewhat later. We examined whether the effectiveness…
Association of Infant Temperament With Subsequent Obesity in Young Children of Mothers With Gestational Diabetes Mellitus
Infant temperament is associated with excess weight gain or childhood obesity risk in samples of healthy individuals, although the evidence has been inconsistent. To our knowledge, no prior research has examined this topic among children exposed to gestational diabetes mellitus…
Gestational weight gain and optimal wellness (GLOW): rationale and methods for a randomized controlled trial of a lifestyle intervention among pregnant women with overweight or obesity
Excess gestational weight gain (GWG) is common among women with overweight or obesity, increasing their risks for pregnancy complications, delivering a large infant, and postpartum weight retention. To date, only intensive interventions have had success and few interventions have been…
Reproductive period and risk of dementia in a diverse cohort of health care members
Women have >50% greater lifetime risk of dementia than men but the role of female-specific endocrine milieu is not well-understood. This study evaluates associations between indicators of estrogen exposure from women's reproductive period and dementia risk in a large diverse…
Association of immunosuppression and HIV viraemia with non-Hodgkin lymphoma risk overall and by subtype in people living with HIV in Canada and the USA: a multicentre cohort study
Research is needed to better understand relations between immunosuppression and HIV viraemia and risk for non-Hodgkin lymphoma, a common cancer in people living with HIV. We aimed to identify key CD4 count and HIV RNA (viral load) predictors of risk…
Incidence of dementia after age 90 in a multiracial cohort
Little is known about dementia incidence in diverse populations of oldest-old, the age group with highest dementia incidence. Incident dementia diagnoses from 1/1/2010 to 9/30/2015 were abstracted from medical records for 2350 members of an integrated health care system in…
Visual outcomes after cataract surgery in patients with type 2 diabetes
To assess the relation between diabetic retinopathy (DR) severity, duration of diabetes, insulin dependence, and preoperative hemoglobin A1c (HbA1c) with visual outcome after phacoemulsification for cataract in patients with type 2 diabetes. Kaiser Permanente Northern California, USA. Retrospective case series.…
Privacy-Protecting Analytical Methods Using Only Aggregate-Level Information to Conduct Multivariable-Adjusted Analysis in Distributed Data Networks
Distributed data networks enable large-scale epidemiologic studies, but protecting privacy while adequately adjusting for a large number of covariates continues to pose methodological challenges. Using 2 empirical examples within a 3-site distributed data network, we tested combinations of 3 aggregate-level…
Comparative effectiveness of treatment of actinic keratosis with topical fluorouracil and imiquimod in the prevention of keratinocyte carcinoma: a cohort study
The effectiveness of 5-fluorouracil compared with that of imiquimod for preventing keratinocyte carcinoma is unknown. To compare the effectiveness of 5-fluorouracil and that of imiquimod in preventing keratinocyte carcinoma in a real-world practice setting. We identified 5700 subjects who filled…
Developing a Prognostic Information System for Personalized Care in Real Time
Electronic medical records hold promise to transform clinical practice. However, technological and other barriers may preclude using them to guide care in real time. We used the Virtual Data Warehouse (VDW) to develop a tool that enables physicians to generate…
Study of Healthy Aging in African Americans (STAR)
Rates of dementia and Alzheimer’s disease are 40% to 100% higher among African Americans compared to non-Hispanic whites. STAR is a longitudinal cohort study of lifecourse vascular risk and brain aging in 700 African Americans ages 50 and older. The goals…
Study of Longevity in Diabetes (SOLID)
Type 1 diabetes is a complicated disease requiring constant adherence to glycemic targets and meticulous attention and vigilance of blood sugar. Individuals with type 1 diabetes are living longer than ever before, yet very little is known about how this…
Kaiser Healthy Aging and Diverse Life Experiences Study (KHANDLE)
Although there are marked ethnic disparities in rates of dementia, almost nothing is known about early-life contributors to dementia in ethnic minority groups, nor if the trajectory of cognitive decline or transition to cognitive impairment varies across ethnic groups. We…
Life After 90
Alzheimer’s disease and other dementias affect 15 percent of those aged 65 and older, by age 90 and older this number increases to a startling 40 to 50 percent. The oldest-old, people aged 90 and older, are the fastest growing…
Maternal Gestational Weight Gain, Obesity, and the Timing of Pubertal Onset in Daughters
Early puberty is associated with adverse health outcomes, but little is known regarding early life determinants influencing pubertal timing. We examined the associations between maternal gestational weight gain (GWG) and the timing of the onset of breast development (thelarche) and…
The association of medical and demographic characteristics with sarcopenia and low muscle radiodensity in patients with nonmetastatic colorectal cancer
Sarcopenia and low skeletal muscle radiodensity (SMD) have been associated with adverse outcomes in patients with colorectal cancer (CRC); however, factors contributing to these 2 muscle abnormalities are unclear. The aim of this study was to investigate the association of…
Trends in marijuana use among pregnant women with and without nausea and vomiting in pregnancy, 2009-2016
Cross-sectional studies indicate an elevated prevalence of prenatal marijuana use in women with nausea and vomiting in pregnancy (NVP). However, it is unknown whether differences in marijuana use by NVP status have persisted over time as marijuana becomes more acceptable…
Lifecourse Health, Cerebral Pathology, and Ethnic Disparities in Dementia
Although there are marked ethnic disparities in rates of dementia, almost nothing is known about early-life contributors to dementia in ethnic minority groups, nor if the trajectory of cognitive decline or transition to cognitive impairment varies across ethnic groups. This…
Use of three summary measures of pediatric vaccination for studying the safety of the childhood immunization schedule
Summary measures such as number of vaccine antigens, number of vaccines, and vaccine aluminum exposure by the 2nd birth day are directly related to parents' concerns that children receive too many vaccines over a brief period. High correlation among summary…
The Be-Well Study: a prospective cohort study of lifestyle and genetic factors to reduce the risk of recurrence and progression of non-muscle-invasive bladder cancer
Bladder cancer is one of the top five cancers diagnosed in the U.S. with a high recurrence rate, and also one of the most expensive cancers to treat over the life-course. However, there are few observational, prospective studies of bladder…
Long-term Risk of Colorectal Cancer and Related Deaths After a Colonoscopy With Normal Findings
Guidelines recommend a 10-year rescreening interval after a colonoscopy with normal findings (negative colonoscopy results), but evidence supporting this recommendation is limited. To examine the long-term risks of colorectal cancer and colorectal cancer deaths after a negative colonoscopy result, in…
Long-Term Outcomes Among Patients Discharged From the Hospital With Moderate Anemia: A Retrospective Cohort Study
Randomized clinical trial findings support decreased red blood cell (RBC) transfusion and short-term tolerance of in-hospital anemia. However, long-term outcomes related to changes in transfusion practice have not been described. To describe the prevalence of anemia at and after hospital…
Patients with complex chronic conditions: Health care use and clinical events associated with access to a patient portal
For patients with diabetes, many with multiple complex chronic conditions, using a patient portal can support self-management and coordination of health care services, and may impact the frequency of in-person health care visits. To examine the impact of portal access…
Potential Effects Of Eliminating The Individual Mandate Penalty In California
The tax penalty for noncompliance with the Affordable Care Act's individual mandate is to be eliminated starting in 2019. We investigated the potential impact of this change on enrollees' decisions to purchase insurance and on individual-market premiums. In a survey…
Kidney function, proteinuria and breast arterial calcification in women without clinical cardiovascular disease: The MINERVA study
Breast arterial calcification (BAC) may be a predictor of cardiovascular events and is highly prevalent in persons with end-stage kidney disease. However, few studies to date have examined the association between mild-to-moderate kidney function and proteinuria with BAC. We prospectively…
Shake Rattle & Roll – Design and rationale for a pragmatic trial to improve blood pressure control among blacks with persistent hypertension
In Kaiser Permanente Northern California (KPNC), members had similar access to care and a very high overall rate of hypertension control. However, blacks had poorer blood pressure (BP) control than whites. The Shake Rattle & Roll (SRR) trial aimed to…
Automated symptom and treatment side effect monitoring for improved quality of life among adults with diabetic peripheral neuropathy in primary care: a pragmatic, cluster, randomized, controlled trial
To evaluate the effectiveness of automated symptom and side effect monitoring on quality of life among individuals with symptomatic diabetic peripheral neuropathy. We conducted a pragmatic, cluster randomized controlled trial (July 2014 to July 2016) within a large healthcare system.…
Recurrence after hospitalization for acute coronary syndrome among HIV-infected and HIV-uninfected individuals
We evaluated the association of HIV infection and immunodeficiency with acute coronary syndrome (ACS) recurrence, and with all-cause mortality as a secondary outcome, after hospitalization for ACS among HIV-infected and HIV-uninfected individuals. We conducted a retrospective cohort study within Kaiser…
Index colonoscopy-related risk factors for postcolonoscopy colorectal cancers
Postcolonoscopy colorectal cancers (PCCRCs) are defined as those detected ≤10 years after an index colonoscopy negative for cancer, but modifiable risk factors are not well established in large, community-based populations. We evaluated risk factors from the index colonoscopy for PCCRCs diagnosed…
Birth in High Infant Mortality States and Dementia Risk in a Cohort of Elderly African American and White Health Care Members
Birth in areas with high infant mortality rates (IMRs) has been linked to worse long-term health outcomes, yet it is completely unknown if it impacts dementia risk. In total 6268 health care members were followed for dementia diagnosis from 1996…
Particulate Air Pollution, Cardiovascular Events, and Susceptibility Factors (PACES)
This is a retrospective cohort study of 5 million adult members of Kaiser Permanente Northern California during 2000 to 2012, linked to state-of-the-art estimates of exposure to PM2.5 (particulate matter less than 2.5 micrometers in diameter) generated at 1km x…
Study on the Association of Uterine Perforation and IUD expulsion With Breastfeeding Status at the Time of IUD insertion and Postpartum Timing of IUD Insertion in Electronic Medical Record Databases – A Post-marketing Requirement for Mirena
The Food and Drug Administration (FDA) has required Bayer AG to conduct a post-marketing study in the U.S. to determine the incidence of uterine perforation and IUD expulsion by type of intrauterine device (IUD) used. The goal of this study…
Patterns of medication adherence in a multi-ethnic cohort of prevalent statin users diagnosed with breast, prostate, or colorectal cancer
To investigate the implications of a cancer diagnosis on medication adherence for pre-existing comorbid conditions, we explored statin adherence patterns prior to and following a new diagnosis of breast, colorectal, or prostate cancer among a multi-ethnic cohort. We identified adults…
Prevalence and predictors of delayed clinical diagnosis of Type 2 diabetes: a longitudinal cohort study
To examine the prevalence and person-level predictors of undiagnosed Type 2 diabetes among adults with elevated HbA1c values. We identified adults without diabetes who had a first elevated HbA1c (index HbA1c ≥ 48 mmol/mol; ≥ 6.5%) between January 2014 and…
Central Obesity Increases the Risk of Gestational Diabetes Partially Through Increasing Insulin Resistance
This study examined the associations of central obesity measures, waist to hip ratio (WHR) and waist circumference (WC), in early pregnancy with subsequent risk of gestational diabetes mellitus (GDM) and evaluated the potential mediating role of insulin resistance markers. Within…
Examining the role of access to care: Racial/ethnic differences in receipt of resection for early-stage non-small cell lung cancer among integrated system members and non-members
To examine the role of uniform access to care in reducing racial/ethnic disparities in receipt of resection for early stage non-small cell lung cancer (NSCLC) by comparing integrated health system member patients to demographically similar non-member patients. Using data from…
Effects of Organized Colorectal Cancer Screening on Cancer Incidence and Mortality in a Large, Community-based Population
Little information is available on the effectiveness of organized colorectal cancer (CRC) screening on screening uptake, incidence, and mortality in community-based populations. We contrasted screening rates, age-adjusted annual CRC incidence, and incidence-based mortality rates before (baseline year 2000) and after…
Association of raltegravir use with long-term health outcomes in HIV-infected patients: an observational post-licensure safety study in a large integrated healthcare system
Raltegravir became the first integrase inhibitor to gain FDA approval; but with limited evidence documenting long-term risks in real world care, especially for major health outcomes of interest. Assess raltegravir safety in clinical practice within an integrated health system. We…
A Pre-Pregnancy Biomarker Risk Score Improves Prediction of Future Gestational Diabetes
Previous studies have not examined the ability of multiple preconception biomarkers, considered together, to improve prediction of gestational diabetes mellitus (GDM). To develop a preconception biomarker risk score and assess its association with subsequent GDM. A nested case-control study among…
Adverse Selection into and within the Individual Health Insurance Market in California in 2014
The Affordable Care Act (ACA) introduced reforms to mitigate adverse selection into and within the individual insurance market. We examined the traits and predicted medical spending of enrollees in California post-ACA. Survey of 2,103 enrollees in individual market plans, on-…
Early Midlife Pulmonary Function and Dementia Risk
Poor pulmonary function (PPF) is associated with increased risk of dementia, yet it is unclear if PPF in early adulthood to midlife increases risk, independent of smoking and subsequent vascular disease. This study evaluated the association between multiple markers of…
Traumatic brain injury associated with dementia risk among people with type 1 diabetes
To examine the association between traumatic brain injury (TBI) and dementia risk among a cohort of middle-aged and elderly individuals with type 1 diabetes (T1D). We evaluated 4,049 members of an integrated health care system with T1D ≥50 years old…
Long-term Glycemic Control and Dementia Risk in Type 1 Diabetes
Individuals with type 1 diabetes have experienced an increase in life expectancy; yet, it is unknown what level of glycemic control is ideal for maintaining late-life brain health. We investigated the association of long-term glycemic control with dementia in older…
Comparison of privacy-protecting analytic and data-sharing methods: A simulation study
Privacy-protecting analytic and data-sharing methods that minimize the disclosure risk of sensitive information are increasingly important due to the growing interest in utilizing data across multiple sources. We conducted a simulation study to examine how avoiding sharing individual-level data in…
Use of non-steroidal anti-inflammatory drugs during pregnancy and the risk of miscarriage
Nonsteroidal antiinflammatory drugs are among the medications most widely used by pregnant women, and previous studies have reported an increased risk of miscarriage that is associated with nonsteroidal antiinflammatory drug use during pregnancy. Although the findings have not always been…
Cutaneous Melanoma Risk among People with HIV in the United States and Canada
Cutaneous melanoma incidence may be modestly elevated in people with HIV (PWH) vs. people without HIV. However, little is known about the relationship of immunosuppression, HIV replication, and antiretroviral therapy (ART) with melanoma risk. PWH of white race in the…
Relative Performance of Propensity Score Matching Strategies for Subgroup Analyses
Postapproval drug safety studies often use propensity scores (PSs) to adjust for a large number of baseline confounders. These studies may involve examining whether treatment safety varies across subgroups. There are many ways a PS could be used to adjust…
Disparities in Initiation of Direct-Acting Antiviral Agents for Hepatitis C Virus Infection in an Insured Population
The cost of direct-acting antiviral agents (DAAs) for hepatitis C virus (HCV) infection may contribute to treatment disparities. However, few data exist on factors associated with DAA initiation. We conducted a retrospective cohort study of HCV-infected Kaiser Permanente Northern California…
Associations Between Maternal Obesity and Pregnancy Hyperglycemia and Timing of Pubertal Onset in Adolescent Girls: A Population-Based Study
Early puberty is associated with adverse health outcomes. We investigated whether in utero exposure to maternal obesity is associated with daughters' pubertal timing using 15,267 racially/ethnically diverse Kaiser Permanente Northern California members aged 6-11 years with pediatrician-assessed Tanner staging (2003-2017).…
Association of Muscle and Adiposity Measured by Computed Tomography With Survival in Patients With Nonmetastatic Breast Cancer
Sarcopenia (low muscle mass), poor muscle quality (low muscle radiodensity), and excess adiposity derived from computed tomography (CT) has been related to higher mortality in patients with metastatic breast cancer, but the association with prognosis in patients with nonmetastatic breast…
High-resolution mapping of traffic related air pollution with Google street view cars and incidence of cardiovascular events within neighborhoods in Oakland, CA
Some studies have linked long-term exposure to traffic related air pollutants (TRAP) with adverse cardiovascular health outcomes; however, previous studies have not linked highly variable concentrations of TRAP measured at street-level within neighborhoods to cardiovascular health outcomes. Long-term pollutant concentrations…
A Cohort Study of Metformin and Colorectal Cancer Risk among Patients with Diabetes Mellitus
Background: Several epidemiologic studies have reported strong inverse associations between metformin use and risk of colorectal cancer, although time-related biases, such as immortal time bias, may in part explain these findings. We reexamined this association using methods to minimize these…
Vaccination Patterns in Children After Autism Spectrum Disorder Diagnosis and in Their Younger Siblings
In recent years, rates of vaccination have been declining. Whether this phenomenon disproportionately affects children with autism spectrum disorder (ASD) or their younger siblings is unknown. To investigate if children after receiving an ASD diagnosis obtain their remaining scheduled vaccines…
Prospective surveillance pilot of rivaroxaban safety within the US Food and Drug Administration Sentinel System
The US Food and Drug Administration's Sentinel system developed tools for sequential surveillance. In patients with non-valvular atrial fibrillation, we sequentially compared outcomes for new users of rivaroxaban versus warfarin, employing propensity score matching and Cox regression. A total of…
Methods for addressing “innocent bystanders” when evaluating safety of concomitant vaccines
The need to develop methods for studying the safety of childhood immunization schedules has been recognized by the Institute of Medicine and Department of Health and Human Services. The recommended childhood immunization schedule includes multiple vaccines in a visit. A…
Bias from outcome misclassification in immunization schedule safety research
The Institute of Medicine recommended conducting observational studies of childhood immunization schedule safety. Such studies could be biased by outcome misclassification, leading to incorrect inferences. Using simulations, we evaluated (1) outcome positive predictive values (PPVs) as indicators of bias of…
Liver Enzymes in Early to Mid-pregnancy, Insulin Resistance, and Gestational Diabetes Risk: A Longitudinal Analysis
Background: Liver enzymes may be implicated in glucose homeostasis; liver enzymes progressively change during pregnancy but longitudinal data during pregnancy in relation to insulin resistance and gestational diabetes (GDM) risk are lacking. We investigated longitudinal associations of γ-glutamyl transferase (GGT)…
An Observational Study of Cardiovascular Risks Associated with Rheumatoid Arthritis Therapies: A Comparison of Two Analytical Approaches
Comparative safety studies typically use hierarchical treatment categories that lump monotherapy and combination therapy. The consequence of this approach on study results is not clear. For example, studies of tumor necrosis factor inhibitors usually lump users regardless of whether they…
A cohort study of maternal cardiometabolic risk factors and primary cesarean delivery in an integrated health system
Maternal cardiometabolic risk factors (i.e., hyperglycemia, pre-existing hypertension and high body mass index) impact fetal growth and risk of having a cesarean delivery. However, the independent and joint contribution of maternal cardiometabolic risk factors to primary cesarean section is unclear.…
Prospective Postmarketing Surveillance of Acute Myocardial Infarction in New Users of Saxagliptin: A Population-Based Study
The cardiovascular safety of saxagliptin, a dipeptidyl-peptidase 4 inhibitor, compared with other antihyperglycemic treatments is not well understood. We prospectively examined the association between saxagliptin use and acute myocardial infarction (AMI). We identified patients aged ≥18 years, starting from the…
A real-world, community-based cohort study comparing the effectiveness of topical fluoruracil vs. topical imiquimod for the treatment of actinic keratosis
The most widely used topical agents for the field-based treatment of multiple actinic keratoses (AKs) are 5-fluorouracil and imiquimod, but their comparative effectiveness has not been assessed in a real-world setting. We compared the effectiveness of 5-fluorouracil and imiquimod in…
Exposure to Magnetic Field Non-Ionizing Radiation and the Risk of Miscarriage: A Prospective Cohort Study
Magnetic field (MF) non-ionizing radiation is widespread and everyone is exposed to some degree. This prospective cohort study of 913 pregnant women examined the association between high MF exposure and miscarriage risk. Cox (proportional hazards) regression was used to examine…
Disparities in Prostate, Lung, Breast, and Colorectal Cancer Survival and Comorbidity Status among Urban American Indians and Alaskan Natives
Cancer is the second leading cause of death among American Indians and Alaskan Natives (AIAN), although cancer survival information in this population is limited, particularly among urban AIAN. In this retrospective cohort study, we compared all-cause and prostate, breast, lung,…
A review of the performance of different methods for propensity score matched subgroup analyses and a summary of their application in peer-reviewed research studies
When evaluating safety signals, there is often interest in understanding safety in all patients for whom compared treatments are reasonable alternatives, as well as in specific subgroups of interest. There are numerous ways that propensity score (PS) matching can be…
Serious infections among a large cohort of subjects with systemically treated psoriasis
Biologic therapy is effective for treatment of moderate-to-severe psoriasis but may be associated with an increased risk for serious infection. To estimate the serious infection rate among patients with psoriasis treated with biologic as compared with nonbiologic systemic agents within…
Age at menarche and late adolescent adiposity associated with mammographic density on processed digital mammograms in 24,840 women
Background: High mammographic density is strongly associated with increased breast cancer risk. Some, but not all, risk factors for breast cancer are also associated with higher mammographic density.Methods: The study cohort (N = 24,840) was drawn from the Research Program…
Survival after dementia diagnosis in five racial/ethnic groups
Information on anticipated survival time after dementia diagnosis among racially/ethnically diverse patients is needed to plan for care and evaluate disparities. Dementia-free health care members aged ≥64 years were followed (1/1/2000-12/31/2013) for dementia diagnosis and subsequent survival (n = 23,032 Asian American; n = 18,778…
Estimating outcomes and cost effectiveness using a single-arm clinical trial: ofatumumab for double-refractory chronic lymphocytic leukemia.
BACKGROUND:Ofatumumab (Arzerra®, Novartis) is a treatment for chronic lymphocytic leukemia refractory to fludarabine and alemtuzumab [double refractory (DR-CLL)]. Ofatumumab was licensed on the basis of an uncontrolled Phase II study, Hx-CD20-406, in which patients receiving ofatumumab survived for a median…
Malignancy rates in a large cohort of patients with systemically treated psoriasis in a managed care population
Moderate to severe psoriasis often requires treatment with systemic agents, many of which have immunosuppressive properties and could increase cancer risk, including nonmelanoma skin cancer (NMSC). We sought to estimate the overall malignancy rate (excluding NMSC) and NMSC rate among…
Association of Testosterone Replacement With Cardiovascular Outcomes Among Men With Androgen Deficiency
Controversy exists regarding the safety of testosterone replacement therapy (TRT) following recent reports of an increased risk of adverse cardiovascular events. To investigate the association between TRT and cardiovascular outcomes in men with androgen deficiency. A retrospective cohort study was…
Software to Automate Implementation of Causal Inference Methods with Time-Varying Interventions
This project aims to develop SAS macros to automate the data structuring required for implementation of Causal Inference methods with electronic health records data in studies with time-varying exposures, confounding and selection bias (e.g., marginal structural modeling with inverse probability…
Feasibility and Performance Assessments of TMLE and hdPS Methodologies to Fit MSM in a Real-World CER Study
This study aims to evaluate the practicability and practical advantages of: 1) Targeted Minimum Loss based Estimation (TMLE), and 2) a high-dimensional propensity score (hdPS) algorithm to fit dynamic Marginal Structural Models (MSM) in a longitudinal comparative effectiveness research (CER)…
Trends in Incidence of Hospitalized Acute Myocardial Infarction in the Cardiovascular Research Network (CVRN)
Monitoring trends in cardiovascular events can provide key insights into the effectiveness of prevention efforts. Leveraging data from electronic health records provides a unique opportunity to examine contemporary, community-based trends in acute myocardial infarction hospitalizations. We examined trends in hospitalized…
Identification of the joint effect of a dynamic treatment intervention and a stochastic monitoring intervention under the no direct effect assumption
The management of chronic conditions is characterized by frequent re-assessment of therapy decisions in response to the patient's changing condition over the course of the illness. Evidence most suitable to inform care thus often concerns the contrast of adaptive treatment…
Proton Pump Inhibitor and Histamine-2 Receptor Antagonist Use and Iron Deficiency
Proton pump inhibitors (PPIs) and histamine-2 receptor antagonists (H2RAs) suppress gastric acid production, which can inhibit iron absorption. However, few data exist regarding whether these medications increase the risk of clinical iron deficiency. A community-based case-control study evaluated the association…
Moderate intensity sports and exercise is associated with glycaemic control in women with gestational diabetes
To assess the association of regular, unsupervised sports and exercise during pregnancy, by intensity level, with glycaemic control in women with gestational diabetes (GDM). Prospective cohort study of 971 women who, shortly after being diagnosed with GDM, completed a Pregnancy Physical…
Supporting Better Choices in California’s Individual Market
Assess "adverse selection" in California's Individual Health Insurance Market by surveying samples of individuals who go online to Covered California and sign up for either a Kaiser product or a product of one of the other major players on the…
Privacy-Preserving Analytic and Data-Sharing Methods for Clinical and Patient-Powered Data Network
Develop privacy-protecting analytic tools for PCOR networks to perform rigorous analyses without sharing potentially identifiable patient-level information. Assess benefits of, and barriers to, implementing these analytic tools in multi-site PCOR studies.
Risk of Uterine Perforation among Women Using different types of IUDs and the Association with Timing of Insertion and Breastfeeding
The goal of the study is to compare the incidence of uterine perforation within 12 months after IUD insertion between: (1) postpartum insertions within 12 months of delivery (with breastfeeding status), (2) post abortion or pregnancy loss IUD insertions and…
Screening Mammography for Free: Impact of Eliminating Cost Sharing on Cancer Screening Rates
To study the impact of eliminating cost sharing for screening mammography on mammography rates in a large Medicare Advantage (MA) health plan which in 2010 eliminated cost sharing in anticipation of the Affordable Care Act mandate. Large MA health maintenance…
simcausal R Package: Conducting Transparent and Reproducible Simulation Studies of Causal Effect Estimation with Complex Longitudinal Data
The simcausal R package is a tool for specification and simulation of complex longitudinal data structures that are based on non-parametric structural equation models. The package aims to provide a flexible tool for simplifying the conduct of transparent and reproducible…
Acute demyelinating events following vaccines – a case centered analysis
Case reports have suggested that vaccines may trigger transverse myelitis (TM) or acute disseminated encephalomyelitis (ADEM), but the evidence for a causal association is inconclusive. We analyzed the association of immunization and subsequent development of TM or ADEM. We identified…
Semi-Parametric Estimation and Inference for the Mean Outcome of the Single Time-Point Intervention in a Causally Connected Population.
AbstractWe study the framework for semi-parametric estimation and statistical inference for the sample average treatment-specific mean effects in observational settings where data are collected on a single network of connected units (e.g., in the presence of interference or spillover). Despite…
Invasive Pneumococcal Disease Among HIV-Infected and HIV-Uninfected Adults in a Large Integrated Healthcare System
It is unclear whether HIV-infected individuals remain at higher risk of invasive pneumococcal disease (IPD) compared with HIV-uninfected individuals. We conducted a cohort study of HIV-infected and demographically matched HIV-uninfected adults within Kaiser Permanente Northern California during the period 1996-2011.…
Risk of cancer in Asian Americans: a Kaiser Permanente cohort study
To supplement published cohort data about incident cancer in Asian Americans (Asians) including risk of specific Asian ethnic groups. A cohort study in 124,193 persons (13,344 Asians) with baseline examination data in 1978-1985 used Cox proportional hazards models with seven…
Narrowing the gap in life expectancy between HIV-infected and HIV-uninfected individuals with access to care
It is unknown if a survival gap remains between HIV-infected and HIV-uninfected individuals with access to care. We conducted a cohort study within Kaiser Permanente California during 1996-2011, using abridged life tables to estimate the expected years of life remaining…
Risks and Predictors of Gastric Adenocarcinoma in Patients with Gastric Intestinal Metaplasia and Dysplasia: A Population-Based Study
Gastric intestinal metaplasia and dysplasia are precursor lesions for adenocarcinoma. The risks of progression to malignancy from these lesions are not well characterized, particularly in the US populations. We identified 4,331 Kaiser Permanente Northern California members who were diagnosed with…
Prevalence of childhood and adolescent overweight and obesity from 2003 to 2010 in an integrated health care delivery system
An observational study of the Kaiser Permanente Northern California (KPNC) BMI coding distributions was conducted to ascertain the trends in overweight and obesity prevalence among KPNC members aged 2-19 between the periods of 2003-2005 and 2009-2010. A decrease in the…
Case centered analysis of Optic Neuritis following vaccines
We evaluated the risk of optic neuritis (ON) after vaccines, using a case-centered analysis, comparing the time since vaccination for the patients with ON with that for all similar vaccinees in a large integrated health plan population. We did not…
Pre-pregnancy adverse lipid profile and subsequent risk of gestational diabetes
Lower low-density lipoprotein (LDL) peak diameter and a predominance of small, dense LDL are associated with type 2 diabetes, but it is unclear whether they are a risk factor for gestational diabetes mellitus (GDM). To evaluate whether prepregnancy lipid profile…
Risk for Hospitalized Heart Failure Among New Users of Saxagliptin, Sitagliptin, and Other Antihyperglycemic Drugs: A Retrospective Cohort Study
Recent postmarketing trials produced conflicting results about the risk for hospitalized heart failure (hHF) associated with dipeptidyl peptidase-4 (DPP-4) inhibitors, creating uncertainty about the safety of these antihyperglycemic agents. To examine the associations of hHF with saxagliptin and sitagliptin. Population-based,…
Moderate and Vigorous Intensity Exercise During Pregnancy and Gestational Weight Gain in Women with Gestational Diabetes
Objectives To estimate the associations of moderate and vigorous intensity exercise during pregnancy with the rate of gestational weight gain (GWG) from gestational diabetes (GDM) diagnosis to delivery, overall and stratified by prepregnancy overweight/obesity. Methods Prospective cohort study with physical…
Intravenous immune globulin and thromboembolic adverse events: A systematic review and meta-analysis of RCTs
Prior case reports and observational studies indicate that intravenous immune globulin (IVIg) products may cause thromboembolic events (TEEs), leading the FDA to require a boxed warning in 2013. The effect of IVIg treatment on the risk of serious TEEs (acute…
A Case Study of the Impact of Data-Adaptive Versus Model-Based Estimation of the Propensity Scores on Causal Inferences from Three Inverse Probability Weighting Estimators
Consistent estimation of causal effects with inverse probability weighting estimators is known to rely on consistent estimation of propensity scores. To alleviate the bias expected from incorrect model specification for these nuisance parameters in observational studies, data-adaptive estimation and in…
Evaluation of propensity scores, disease risk scores, and regression in confounder adjustment for the safety of emerging treatment with group sequential monitoring
The objective of this study was to evaluate regression, matching, and stratification on propensity score (PS) or disease risk score (DRS) in a setting of sequential analyses where statistical hypotheses are tested multiple times. In a setting of sequential analyses,…
Waning Tdap Effectiveness in Adolescents
Because the effectiveness of diphtheria-tetanus-acellular pertussis (DTaP) vaccine wanes substantially after the fifth dose at ages 4 to 6 years, there is a growing cohort of adolescents who rely on tetanus toxoid, reduced diphtheria toxoid, and acellular pertussis (Tdap) for…
Gene by Environment Investigation of Incident Lung Cancer Risk in African-Americans
Genome-wide association studies have identified polymorphisms linked to both smoking exposure and risk of lung cancer. The degree to which lung cancer risk is driven by increased smoking, genetics, or gene-environment interactions is not well understood. We analyzed associations between…
Adherence to Metformin, Statins, and ACE/ARBs Within the Diabetes Health Plan (DHP)
Reducing patient cost-sharing and engaging patients in disease management activities have been shown to increase uptake of evidence-based care. To evaluate the effect of employer purchase of a disease-specific plan with reduced cost-sharing and disease management (the Diabetes Health Plan/DHP)…
Balancing Score Adjusted Targeted Minimum Loss-based Estimation
Adjusting for a balancing score is sufficient for bias reduction when estimating causal effects including the average treatment effect and effect among the treated. Estimators that adjust for the propensity score in a nonparametric way, such as matching on an…
Breastfeeding, PAM50 Tumor Subtype, and Breast Cancer Prognosis and Survival
Breastfeeding is associated with decreased breast cancer risk, yet associations with prognosis and survival by tumor subtype are largely unknown. We conducted a cohort study of 1636 women from two prospective breast cancer cohorts. Intrinsic tumor subtype (luminal A, luminal…
Significant Racial Disparities Exist in Noncardia Gastric Cancer Outcomes Among Kaiser Permanente’s Patient Population
Racial and ethnic differences in gastric cancer are not well understood. This study sought to compare the clinicopathological features and survival of noncardia gastric adenocarcinoma (NCGA) patients with different racial/ethnic backgrounds in Kaiser Permanente Northern California (KPNC), a large integrated…
High-dimensional propensity score algorithm in comparative effectiveness research with time-varying interventions
The high-dimensional propensity score (hdPS) algorithm was proposed for automation of confounding adjustment in problems involving large healthcare databases. It has been evaluated in comparative effectiveness research (CER) with point treatments to handle baseline confounding through matching or covariance adjustment…
Does adopting a prenatal substance use protocol reduce racial disparities in CPS reporting related to maternal drug use? A California case study
This study examined whether adopting a standardized prenatal substance use protocol (protocol) in a hospital labor and delivery unit reduced racial disparities in reporting to child protective services (CPS) related to maternal drug use during pregnancy. This study used an…
Risk of Cardiovascular Disease Associated With a Restless Legs Syndrome Diagnosis in a Retrospective Cohort Study from Kaiser Permanente Northern California
Recent cross-sectional studies suggest that restless legs syndrome (RLS) may be associated with an increased prevalence of cardiovascular disease (CVD) comorbidity or risk factors. We evaluated whether primary or secondary RLS was associated with an increased risk of incident cardiovascular…
Alcohol Intake, Beverage Choice, and Cancer: A Cohort Study in a Large Kaiser Permanente Population
The authors studied incident cancer risk from 1978 to 1985 and through follow-up in 2012 relative to light-to-moderate and heavy drinking and to the choice of alcoholic beverage in a cohort of 124,193 persons. With lifelong abstainers as referent, heavy…
Network meta-analysis incorporating randomized controlled trials and non-randomized comparative cohort studies for assessing the safety and effectiveness of medical treatments: challenges and opportunities
Network meta-analysis is increasingly used to allow comparison of multiple treatment alternatives simultaneously, some of which may not have been compared directly in primary research studies. The majority of network meta-analyses published to date have incorporated data from randomized controlled…
Impact of age on clinicopathological features and survival of patients with noncardia gastric adenocarcinoma
Gastric cancer often occurs in the elderly but is uncommon in young individuals. Whether young patients have different clinical behaviors and outcomes from those of older patients remain unclear. We identified 1,366 cases of newly diagnosed noncardia gastric adenocarcinoma from…
Higher Levels of Cystatin C Are Associated with Worse Cognitive Function in Older Adults with Chronic Kidney Disease: The Chronic Renal Insufficiency Cohort Cognitive Study
To determine the association between cognition and levels of cystatin C in persons with chronic kidney disease (CKD). Prospective observational study. Chronic Renal Insufficiency Cohort Cognitive Study. Individuals with a baseline cognitive assessment completed at the same visit as serum…
Targeted learning in real-world comparative effectiveness research with time-varying interventions
In comparative effectiveness research (CER), often the aim is to contrast survival outcomes between exposure groups defined by time-varying interventions. With observational data, standard regression analyses (e.g., Cox modeling) cannot account for time-dependent confounders on causal pathways between exposures and…
Intensive residential treatment for severe obsessive-compulsive disorder: characterizing treatment course and predictors of response.
BACKGROUND:Intensive residential treatment (IRT) is effective for severe, treatment-resistant obsessive-compulsive disorder (OCD). We sought to characterize predictors and course of response to IRT.METHODS:Admission, monthly, and discharge data were collected on individuals receiving IRT. We examined the association between baseline characteristics…
Intrinsic subtypes from PAM50 gene expression assay in a population-based breast cancer cohort: Differences by age, race, and tumor characteristics
Data are lacking to describe gene expression-based breast cancer intrinsic subtype patterns for population-based patient groups. We studied a diverse cohort of women with breast cancer from the Life After Cancer Epidemiology and Pathways studies. RNA was extracted from 1…
Long-term outcomes among African-American and white women with breast cancer: what is the impact of comorbidity?
OBJECTIVES: We examined the association between comorbidity and long-term mortality from breast cancer and other causes among African-American and white women with breast cancer.METHODS: A total of 170 African-American and 829 white women aged 40-84years were followed for up to…
A pragmatic cluster randomized clinical trial of diabetes prevention strategies for women with gestational diabetes: design and rationale of the Gestational Diabetes’ Effects on Moms (GEM) study
Women with gestational diabetes (GDM) are at high risk of developing diabetes later in life. After a GDM diagnosis, women receive prenatal care to control their blood glucose levels via diet, physical activity and medications. Continuing such lifestyle skills into…
Accuracy of hemoglobin A1c imputation using fasting plasma glucose in diabetes research using electronic health records data
In studies that use electronic health record data, imputation of important data elements such as Glycated hemoglobin (A1c) has become common. However, few studies have systematically examined the validity of various imputation strategies for missing A1c values. We derived a…
Prevalence and Neonatal Factors Associated with Autism Spectrum Disorders in Preterm Infants
To determine the prevalence of autism spectrum disorders (ASD) across gestational age, examine the risk of ASD by gestational age controlling for other risk factors, and identify potential risk factors in the neonatal intensive care unit. A retrospective cohort of…
Do Medicare Advantage plans select enrollees in higher margin clinical categories?
The CMS-HCC risk adjustment system for Medicare Advantage (MA) plans calculates weights, which are effectively relative prices, for beneficiaries with different observable characteristics. To do so it uses the relative amounts spent per beneficiary with those characteristics in Traditional Medicare…
Impact of Specific Glucose-Control Strategies on Microvascular and Macrovascular Outcomes in 58,000 Adults With Type 2 Diabetes
Comparative effectiveness research methods are used to compare the effect of four distinct glucose-control strategies on subsequent myocardial infarction and nephropathy in type 2 diabetes. A total of 58,000 adults with type 2 diabetes and A1C
Multivariable confounding adjustment in distributed data networks without sharing of patient-level data
It is increasingly necessary to analyze data from multiple sources when conducting public health safety surveillance or comparative effectiveness research. However, security, privacy, proprietary, and legal concerns often reduce data holders' willingness to share highly granular information. We describe and…
Socioeconomic Status and Lung Cancer: Unraveling the Contribution of Genetic Admixture
OBJECTIVES: We examined the relationship between genetic ancestry, socioeconomic status (SES), and lung cancer among African Americans and Latinos. METHODS: We evaluated SES and genetic ancestry in a Northern California lung cancer case-control study (1998-2003) of African Americans and Latinos.…
Implementation of an outpatient electronic health record and emergency department visits, hospitalizations, and office visits among patients with diabetes
IMPORTANCE: The US federal government is spending billions of dollars in physician incentives to encourage the meaningful use of electronic health records (EHRs). Although the use of EHRs has potential to improve patient health outcomes, the existing evidence has been…
Super learning to hedge against incorrect inference from arbitrary parametric assumptions in marginal structural modeling
OBJECTIVE: Clinical trials are unlikely to ever be launched for many comparative effectiveness research (CER) questions. Inferences from hypothetical randomized trials may however be emulated with marginal structural modeling (MSM) using observational data, but success in adjusting for time-dependent confounding…
Confounding adjustment in comparative effectiveness research conducted within distributed research networks
BACKGROUND: A distributed research network (DRN) of electronic health care databases, in which data reside behind the firewall of each data partner, can support a wide range of comparative effectiveness research (CER) activities. An essential component of a fully functional…
Targeted maximum likelihood estimation in safety analysis
OBJECTIVES: To compare the performance of a targeted maximum likelihood estimator (TMLE) and a collaborative TMLE (CTMLE) to other estimators in a drug safety analysis, including a regression-based estimator, propensity score (PS)-based estimators, and an alternate doubly robust (DR) estimator…
Adverse Clinical Events Among Medicare Beneficiaries Using Antipsychotic Drugs: Linking Health Insurance Benefits and Clinical Needs
OBJECTIVE: Medicare Part D provides formulary protections for antipsychotics but does not exempt these drugs from cost-sharing. We investigated the impact of Part D coverage on antipsychotic drug spending, adherence, and clinical outcomes among beneficiaries with varying indications for use.…
Effectiveness and Reach of the FLU-FIT Program in an Integrated Health Care System: A Multisite Randomized Trial
OBJECTIVES: We tested the effectiveness of offering home fecal immunochemical tests (FITs) during influenza vaccination clinics to increase colorectal cancer screening (CRCS). METHODS: In a clinical trial at Kaiser Permanente Northern California influenza clinics in Redwood City, Richmond, South San…
Technical evaluation of methods for identifying chemotherapy-induced febrile neutropenia in healthcare claims databases.
BACKGROUND:Healthcare claims databases have been used in several studies to characterize the risk and burden of chemotherapy-induced febrile neutropenia (FN) and effectiveness of colony-stimulating factors against FN. The accuracy of methods previously used to identify FN in such databases has…
Retinopathy and Cognitive Impairment in Adults With CKD
BACKGROUND: Retinal microvascular abnormalities have been associated with cognitive impairment, possibly serving as a marker of cerebral small-vessel disease. This relationship has not been evaluated in persons with chronic kidney disease (CKD), a condition associated with increased risk of both…
Impact of type 2 diabetes on lower urinary tract symptoms in men: a cohort study
BACKGROUND: Studies of the impact of type 2 diabetes on the prevalence and incidence of lower urinary tract symptoms (LUTS) among men have provided divergent results. We sought to examine this issue using two large and diverse cohorts. METHODS: This…
Social networks, social support, and burden in relationships, and mortality after breast cancer diagnosis in the Life After Breast Cancer Epidemiology (LACE) Study
Larger social networks have been associated with lower breast cancer mortality. The authors evaluated how levels of social support and burden influenced this association. We included 2,264 women from the Life After Cancer Epidemiology study who were diagnosed with early-stage,…
Neisseria gonorrhea and Chlamydia trachomatis Screening at Intrauterine Device Insertion and Pelvic Inflammatory Disease
OBJECTIVE: To evaluate the relationship between Neisseria gonorrhea and Chlamydia trachomatis screening strategies and risk of pelvic inflammatory disease (PID) after intrauterine device (IUD) insertion. METHODS: We conducted a retrospective cohort study of all IUD insertions at Kaiser Permanente Northern…
Patient awareness and knowledge of breast cancer-related lymphedema in a large, integrated health care delivery system
Breast cancer patients have voiced dissatisfaction regarding their education on breast cancer-related lymphedema risk and risk reduction strategies from their clinicians. Informing patients about lymphedema can contribute to decrease their risk of developing the condition, or among those already affected,…
Cigarette Smoking Associated With Lung Adenocarcinoma In Situ in a Large Case-Control Study (SFBALCS)
INTRODUCTION:: Adenocarcinoma in situ (AIS), formerly bronchioloalveolar carcinoma, is an uncommon subtype of lung adenocarcinoma and accounts for approximately 3% to 4% of lung cancers. Compared with other lung cancer histologies, AIS patients are less likely to be smokers, yet…
Influence of breastfeeding during the postpartum oral glucose tolerance test on plasma glucose and insulin
OBJECTIVE: To examine the effect of breastfeeding during the postpartum oral glucose tolerance test (OGTT) on maternal blood glucose and insulin among women with recent gestational diabetes mellitus. METHODS: Participants were enrolled in the Study of Women, Infant Feeding, and…
Causal inference in epidemiological studies with strong confounding
One of the identifiability assumptions of causal effects defined by marginal structural model (MSM) parameters is the experimental treatment assignment (ETA) assumption. Practical violations of this assumption frequently occur in data analysis when certain exposures are rarely observed within some…
Plasma signaling proteins in persons at genetic risk for Alzheimer disease: influence of APOE genotype.
OBJECTIVE:To study the effect of familial Alzheimer disease (FAD) mutations and APOE genotype on plasma signaling protein levels.DESIGN:Cross-sectional comparison of plasma levels of 77 proteins measured using multiplex immune assays.SETTING:A tertiary referral dementia research center.PARTICIPANTS:Thirty-three persons from families harboring PSEN1…
The value of additional pathology comments indicating suspicion of adenocarcinoma among women diagnosed preoperatively with complex atypical endometrial hyperplasia
Over 40% of women with a preoperative diagnosis of complex atypical hyperplasia (CAH) will have endometrial cancer at hysterectomy. CAH diagnoses are often qualified by comments indicating suspicion of cancer. We examine whether these comments correlate with cancer found at…
Dynamic marginal structural modeling to evaluate the comparative effectiveness of more or less aggressive treatment intensification strategies in adults with type 2 diabetes
PURPOSE: Chronic disease care typically involves treatment decisions that are frequently adjusted to the patient's evolving clinical course (e.g., hemoglobin A1c monitoring and treatment intensification in diabetes patients). Thus, in comparative effectiveness and safety research (CER), it often is less…
Estimating sample sizes for predementia Alzheimer’s trials based on the Alzheimer’s Disease Neuroimaging Initiative
This study modeled predementia Alzheimer's disease clinical trials. Longitudinal data from cognitively normal (CN) and mild cognitive impairment (MCI) participants in the Alzheimer's Disease Neuroimaging Initiative were used to calculate sample size requirements for trials using outcome measures, including the…
Single-institution, multidisciplinary experience with surgical resection of primary chest wall sarcomas.
INTRODUCTION:Primary chest wall sarcomas are rare mesenchymal tumors and their mainstay of therapy is wide surgical resection. We report our single-institution, multidisciplinary experience with full-thickness resection for primary chest wall sarcomas.METHODS:A retrospective review of our prospectively maintained databases revealed that…
Evaluation of a Cell Phone-Based Physical Activity Diary
PURPOSE: Physical activity (PA) diaries reduce the recall error inherent in self-reported PA but are burdensome. The purpose of this study was to compare a cell phone-based diary with a paper diary and examine the reliability and validity of the…
Provision of Contraceptive Services to Women with Diabetes Mellitus
BACKGROUND: Women with diabetes mellitus who delay pregnancy until glycemic control is achieved experience lower rates of adverse pregnancy outcomes. OBJECTIVE: To compare rates of provision of contraceptive services among women with diabetes mellitus and women without chronic medical conditions.…
Clinician awareness and knowledge of breast cancer-related lymphedema in a large, integrated health care delivery setting
Breast cancer survivors have reported dissatisfaction regarding their education on risk of breast cancer-related lymphedema (BCRL) from clinicians. We describe clinician knowledge and treatment referral of patients with BCRL among active oncologists, surgeons, and primary care physicians in the Kaiser…
Lactation Intensity and Postpartum Maternal Glucose Tolerance and Insulin Resistance in Women With Recent GDM: The SWIFT cohort
OBJECTIVE: To examine the association between breastfeeding intensity in relation to maternal blood glucose and insulin and glucose intolerance based on the postpartum 2-h 75-g oral glucose tolerance test (OGTT) results at 6-9 weeks after a pregnancy with gestational diabetes…
Dermatologic care in the homeless and underserved populations: observations from the Venice Family Clinic
Dermatologic care in the homeless and impoverished urban underserved populations is rarely described despite the wide prevalence of skin concerns in this population. Because the homeless population may be subject to increased sun exposure compared to the nonhomeless population, they…
Challenges in the design and analysis of sequentially monitored postmarket safety surveillance evaluations using electronic observational health care data
PURPOSE: Many challenges arise when conducting a sequentially monitored medical product safety surveillance evaluation using observational electronic data captured during routine care. We review existing sequential approaches for potential use in this setting, including a continuous sequential testing method that…
Design considerations in an active medical product safety monitoring system
Active medical product monitoring systems, such as the Sentinel System, will utilize electronic healthcare data captured during routine health care. Safety signals that arise from these data may be spurious because of chance or bias, particularly confounding bias, given the…
When should case-only designs be used for safety monitoring of medical products?
PURPOSE: To assess case-only designs for surveillance with administrative databases. METHODS: We reviewed literature on two designs that are observational analogs to crossover experiments: the self-controlled case series (SCCS) and the case-crossover (CCO) design. RESULTS: SCCS views the 'experiment' prospectively,…
Early start: a cost-beneficial perinatal substance abuse program
OBJECTIVE: To conduct a cost-benefit analysis of Early Start, an integrated prenatal intervention program for stopping substance use in pregnancy. METHODS: A retrospective cohort study was conducted of 49,261 women who had completed prenatal substance abuse screening questionnaires at obstetric…
A case-control study of asphalt and tar exposure and lung cancer in minorities
OBJECTIVES: Considerable controversy surrounds the carcinogenic potential of asphalt and tar. Since minority individuals may have had relatively high historical exposures, we investigated asphalt and tar exposure and lung cancer risk among African Americans and Latino Americans. METHODS: We conducted…
Robust extraction of covariate information to improve estimation efficiency in randomized trials
In randomized trials, investigators typically rely upon an unadjusted estimate of the mean outcome within each treatment arm to draw causal inferences. Statisticians have underscored the gain in efficiency that can be achieved from covariate adjustment in randomized trials with…
A predictive model to help identify intimate partner violence based on diagnoses and phone calls
BACKGROUND: Intimate partner violence (IPV) is a significant health problem but goes largely undiagnosed, undisclosed, and clinically undocumented. PURPOSE: To use historical data on diagnoses and telephone advice calls to develop a predictive model that identifies clinical profiles of women…
Cost-effectiveness of lapatinib plus capecitabine in women with HER2+ metastatic breast cancer who have received prior therapy with trastuzumab.
BACKGROUND:In a phase III trial of women with HER2+ metastatic breast cancer (MBC) previously treated with trastuzumab, an anthracycline, and taxanes (EGF100151), lapatinib plus capecitabine (L+C) improved time to progression (TTP) versus capecitabine monotherapy (C-only). In a trial including HER2+…
Development of disability in chronic obstructive pulmonary disease: beyond lung function
BACKGROUND: COPD is a major cause of disability, but little is known about how disability develops in this condition. METHODS: The authors analysed data from the Function, Living, Outcomes and Work (FLOW) Study which enrolled 1202 Kaiser Permanente Northern California…
Coffee, caffeine, and risk of hospitalization for arrhythmias
Context: Population study data about relations of coffee drinking to arrhythmia are sparse.Objective: To study relations of coffee drinking to risk of cardiac arrhythmia in 130,054 persons with previous data about coffee habits.Design and Outcome Measure: We used Cox proportional…
The MCCB impairment profile for schizophrenia outpatients: results from the MATRICS psychometric and standardization study
The MATRICS Psychometric and Standardization Study was conducted as a final stage in the development of the MATRICS Consensus Cognitive Battery (MCCB). The study included 176 persons with schizophrenia or schizoaffective disorder and 300 community residents. Data were analyzed to…
Fixing flaws in Medicare drug coverage that prompt insurers to avoid low-income patients
Since 2006 numerous insurers have stopped serving the low-income segment of the Medicare Part D program, forcing millions of beneficiaries to change prescription drug plans. Using data from participating plans, we found that Medicare payments do not sufficiently reimburse insurers…
Mammographic density and risk of second breast cancer after ductal carcinoma in situ
BACKGROUND: We examined whether mammographic density predicts risk of second breast cancers among patients with ductal carcinoma in situ (DCIS). METHODS: The study included DCIS patients diagnosed during 1990 to 1997 and treated with breast-conserving surgery at Kaiser Permanente Northern…
Fine mapping of chromosome 15q25.1 lung cancer susceptibility in African-Americans
Several genome-wide association studies identified the chr15q25.1 region, which includes three nicotinic cholinergic receptor genes (CHRNA5-B4) and the cell proliferation gene (PSMA4), for its association with lung cancer risk in Caucasians. A haplotype and its tagging single nucleotide polymorphisms (SNPs)…
Cost-effectiveness of zoledronic acid plus endocrine therapy in premenopausal women with hormone-responsive early breast cancer.
PURPOSE:The aim of this study was to estimate the cost-effectiveness of adding zoledronic acid 4 mg intravenously every 6 months to endocrine therapy in premenopausal women with hormone receptor-positive early breast cancer from a US health care system perspective.MATERIALS AND…
Availability and accuracy of medical record information on language usage of cancer patients from a multi-ethnic population
Documentation of language usage in medical settings could be effective in identifying and addressing language barriers and would improve understanding of health disparities. This study evaluated the availability and accuracy of medical records information on language for 1,664 cancer patients…
Proton pump inhibitors and histamine-2 receptor antagonists are associated with hip fractures among at-risk patients
BACKGROUND & AIMS: Drugs that inhibit gastric acid might increase the risk of hip fracture. However, little long-term exposure data exist and no large studies have been conducted in the United States. METHODS: We conducted a case-control study using data…
Ambient ozone concentrations and cardiac mortality in Southern California 1983-2000: application of a new marginal structural model approach
The authors evaluated the association between ambient ozone levels and cardiac mortality in California's South Coast Air Basin during the period 1983-2000 and compared inferences from several types of marginal structural model (MSM) estimators. The authors undertook an ecologic study…
Association of prediagnostic serum vitamin D levels with the development of basal cell carcinoma
We investigated the association between serum 25-hydroxyvitamin D (25(OH)D) levels and basal cell carcinoma (BCC) risk in a nested case-control study at Kaiser Permanente Northern California (KPNC). A total of 220 case patients with BCC diagnosed after serum collection were…
Pregnancy outcomes by pregnancy intention in a managed care setting
OBJECTIVES: Published studies show poor pregnancy outcomes associated with unintended pregnancies are disproportionately higher than in planned pregnancies and place a burden on the health care system. This study was designed to compare pregnancy intention rates, compare sociodemographic characteristics of…
Clinical features in early Parkinson disease and survival
OBJECTIVE: To examine the association between demographic and clinical features in early Parkinson disease (PD) and length of survival in a multiethnic population. DESIGN: Clinical features within 2 years of diagnosis were determined for an inception cohort established during 1994-1995.…
Alcohol consumption and risk of hematologic malignancies
PURPOSE: Limited data suggest that alcohol drinking may have an inverse relation to risk of non-Hodgkin's lymphoma (NHL). Prospective data about alcohol, NHL, and other hematologic malignancies (HM) are sparse. METHODS: We carried out a cohort study in a multiethnic…
Cost-effectiveness of aliskiren in type 2 diabetes, hypertension, and albuminuria.
The Aliskiren in the Evaluation of Proteinuria in Diabetes (AVOID) trial demonstrated that adding aliskiren, an oral direct renin inhibitor, at a dosage of 300 mg/d to the highest approved dosage of losartan and optimal antihypertensive therapy reduces albuminuria over…
Complex atypical endometrial hyperplasia: the risk of unrecognized adenocarcinoma and value of preoperative dilation and curettage
OBJECTIVE: To evaluate whether preoperative dilation and curettage (D&C) lowers the risk of unexpected cancer at hysterectomy. METHODS: Women with complex atypical endometrial hyperplasia on sampling from January 2000 to May 2008 who underwent hysterectomy within 6 months were identified…
Cost of routine immunization of young children against rotavirus infection with Rotarix versus RotaTeq.
Using a probabilistic model of the clinical and economic burden of rotavirus gastroenteritis (RVGE), we estimated the expected impact of vaccinating a US birth cohort with Rotarix in lieu of RotaTeq. Assuming full vaccination of all children, use of Rotarix…
Cost-effectiveness of pregabalin versus venlafaxine in the treatment of generalized anxiety disorder: findings from a Spanish perspective.
The objective of the present study was to describe a new model of the cost-effectiveness of treatment of generalized anxiety disorder (GAD) and its application to a comparison of pregabalin versus venlafaxine extended-release (XR) from a Spanish healthcare perspective. Microsimulation…
Improving diet and physical activity with ALIVE: a worksite randomized trial
CONTEXT: Healthy diets and regular physical activity confer many health benefits, but the prevalence of these behaviors is relatively low. BACKGROUND: Cost-effective strategies are needed to increase healthy eating and physical activity in the population. DESIGN: An RCT, conducted in…
Hypoglycemic episodes and risk of dementia in older patients with type 2 diabetes mellitus
CONTEXT: Although acute hypoglycemia may be associated with cognitive impairment in children with type 1 diabetes, no studies to date have evaluated whether hypoglycemia is a risk factor for dementia in older patients with type 2 diabetes. OBJECTIVE: To determine…
Cigarette smoking and the risk of Barrett’s esophagus
INTRODUCTION: We examined the association between smoking and the risk of Barrett's esophagus (BE), a metaplastic precursor to esophageal adenocarcinoma. METHODS: We conducted a case-control study within the Kaiser Permanente Northern California population. Patients with a new diagnosis of BE…
CYP1A1/2 haplotypes and lung cancer and assessment of confounding by population stratification
Prior studies of lung cancer and CYP1A1/2 in African-American and Latino populations have shown inconsistent results and have not yet investigated the haplotype block structure of CYP1A1/2 or addressed potential population stratification. To investigate haplotypes in the CYP1A1/2 region and…
Distributing $800 billion: an early assessment of Medicare Part D risk adjustment
The viability and stability of the Medicare Part D prescription drug program depend on accurate risk-adjusted payments. The current approach, prescription drug hierarchical condition categories (RxHCCs), uses diagnosis and demographic information to predict future drug costs. We evaluated the performance…
Using drink size to talk about drinking during pregnancy: a randomized clinical trial of Early Start Plus
This clinical trial compared two brief alcohol use interventions in prenatal clinics: Early Start (ES), a substance-abuse screening and treatment program integrated with prenatal care focused on abstention (n=298), and Early Start Plus (ESP), adding a computerized drink-size assessment tool…
Base excision repair genes and risk of lung cancer among San Francisco Bay Area Latinos and African-Americans
Base excision repair (BER) is the primary DNA damage repair mechanism for repairing small base lesions resulting from oxidation and alkylation damage. This study examines the association between 24 single-nucleotide polymorphisms (SNPs) belonging to five BER genes (XRCC1, APEX1, PARP1,…
Iron intake and body iron stores as risk factors for Barrett’s esophagus: a community-based study
OBJECTIVE: High iron stores are a proposed modifiable risk factor for esophageal adenocarcinoma, but minimal human data exist. We evaluated whether iron intake and iron stores were associated with Barrett's esophagus, a metaplastic change that is a strong risk factor…
Comparison of statistical methods for estimating genetic admixture in a lung cancer study of African Americans and Latinos
A variety of methods are available for estimating genetic admixture proportions in populations; however, few investigators have conducted detailed comparisons using empirical data. The authors characterized admixture proportions among self-identified African Americans (n = 535) and Latinos (n = 412)…
Nucleotide excision repair genes and risk of lung cancer among San Francisco Bay Area Latinos and African Americans
Few studies on the association between nucleotide excision repair (NER) variants and lung cancer risk have included Latinos and African Americans. We examine variants in 6 NER genes (ERCC2, ERCC4, ERCC5, LIG1, RAD23B and XPC) in association with primary lung…
Substance abuse treatment linked with prenatal visits improves perinatal outcomes: a new standard
OBJECTIVE: To evaluate the impact of Early Start, an obstetric clinic-based prenatal substance abuse treatment program, on perinatal outcomes. STUDY DESIGN: Subjects were 49 985 women who completed Prenatal Substance Abuse Screening Questionnaires at obstetric clinics between 1 January 1999…
Cost-effectiveness of abatacept in patients with moderately to severely active rheumatoid arthritis and inadequate response to tumor necrosis factor-alpha antagonists.
OBJECTIVE:To assess cost-effectiveness of abatacept in patients with rheumatoid arthritis (RA) with inadequate response to tumor necrosis factor-alpha antagonists (anti-TNF).METHODS:We developed a simulation model to depict progression of disability [in terms of Health Assessment Questionnaire Disability Index (HAQ-DI)] in women…
Medicare beneficiaries’ knowledge of Part D prescription drug program benefits and responses to drug costs
CONTEXT: Medicare Part D drug benefits include substantial cost sharing. OBJECTIVE: To determine beneficiaries' knowledge of benefits and cost responses. DESIGN, SETTING, AND PARTICIPANTS: Telephone interviews were conducted in 2007 in a stratified random sample of community-dwelling Kaiser Permanente-Northern California…
Cost-effectiveness of abatacept in patients with moderately to severely active rheumatoid arthritis and inadequate response to methotrexate.
OBJECTIVE:To assess cost-effectiveness of abatacept in patients with moderately to severely active RA and inadequate response to MTX.METHODS:We developed a simulation model to depict progression of disability [in terms of the HAQ Disability Index (HAQ-DI)] in women aged 55-64 yrs…
Dietary patterns and the risk of Barrett’s esophagus
The objective of this study was to examine the associations between dietary patterns and the risk of Barrett's esophagus, a precursor to esophageal adenocarcinoma. The authors conducted a case-control study within the Kaiser Permanente Northern California population between 2002 and…
Effects of depression and selective serotonin reuptake inhibitor use on adherence to highly active antiretroviral therapy and on clinical outcomes in HIV-infected patients
OBJECTIVES: To determine the impact of depression on highly active antiretroviral therapy (HAART) adherence and clinical measures and investigate if selective serotonin reuptake inhibitors (SSRIs) improve these measures. DESIGN: Retrospective cohort study. METHODS: In 2 large health maintenance organizations, we…
Development of Alive! (A Lifestyle Intervention Via Email), and its effect on health-related quality of life, presenteeism, and other behavioral outcomes: randomized controlled trial
BACKGROUND: Cost-effective interventions to improve diet and physical activity are a public health priority. Alive! is an email-based intervention to increase physical activity, reduce saturated and trans fats and added sugars, and increase fruit and vegetable consumption. It was shown…
Medical therapy for diabetes is associated with increased use of lower endoscopy
BACKGROUND: Diabetes mellitus is associated with an increased risk of colorectal neoplasia and diabetes medications may further influence the risk. Observational studies of the effect of diabetes medications on colonic neoplasia may be biased if use of diabetes medications is…
Documentation of contraception and pregnancy when prescribing potentially teratogenic medications for reproductive-age women
BACKGROUND: Certain medications are identified by the U.S. Food and Drug Administration (FDA) as class D or X because they increase the risk for birth defects if used during pregnancy. OBJECTIVE: To assess pregnancy rates and the frequency of contraceptive…
Cost-effectiveness of letrozole versus tamoxifen as initial adjuvant therapy in postmenopausal women with hormone-receptor positive early breast cancer from a Canadian perspective.
BACKGROUND:In the primary core analysis of BIG 1-98, a randomized, double-blind trial comparing 5 years of initial adjuvant therapy with letrozole versus tamoxifen in postmenopausal women with hormone receptor-positive (HR+) early breast cancer, letrozole significantly improved disease-free survival by 19%…
Cost-effectiveness of letrozole versus tamoxifen as initial adjuvant therapy in hormone receptor-positive postmenopausal women with early-stage breast cancer.
BACKGROUND:In Breast International Group (BIG) 1-98, a randomized, double-blind trial comparing 5 years of initial adjuvant therapy with letrozole versus tamoxifen in postmenopausal women with hormone receptor-positive early breast cancer, letrozole significantly improved disease-free survival by 19% and reduced risk…
Changes in rates of hysterectomy and uterine conserving procedures for treatment of uterine leiomyoma
OBJECTIVE: The purpose of this study was to investigate treatment of uterine leiomyoma by hysterectomy and uterine conserving procedures (UCPs). STUDY DESIGN: Data from Kaiser Permanente Northern California members undergoing hysterectomy, myomectomy, uterine artery embolization (UAE) and endometrial ablation (EA)…
Predictors of hysterectomy after uterine artery embolization for leiomyoma
OBJECTIVE: This study was undertaken to describe long-term outcomes after uterine artery embolization for leiomyoma. STUDY DESIGN: Data from Kaiser Permanente Northern California members undergoing uterine artery embolization for leiomyoma before July 2001 were collected. Survival analysis was performed to…
The prevalence, burden, and treatment of urinary incontinence among women in a managed care plan
OBJECTIVE: Urinary incontinence (UI) symptoms are common among women, yet only a small proportion of women with incontinence receive a diagnosis and treatment. We used survey and utilization data to determine the prevalence, burden, and treatment use for incontinence among…
Intrauterine contraception: evaluation of clinician practice patterns in Kaiser Permanente Northern California
BACKGROUND: Despite the medical evidence, few women of reproductive age in the United States use intrauterine contraception (IUC) in comparison with women worldwide. To reduce cost as a barrier, Kaiser Permanente removed the cost to the patient for IUC throughout…
Cost effectiveness of once-daily oral chelation therapy with deferasirox versus infusional deferoxamine in transfusion-dependent thalassaemia patients: US healthcare system perspective.
BACKGROUND:Deferasirox is a recently approved once-daily oral iron chelator that has been shown to reduce liver iron concentrations and serum ferritin levels to a similar extent as infusional deferoxamine.OBJECTIVE:To determine the cost effectiveness of deferasirox versus deferoxamine in patients with…
Causal inference in longitudinal studies with history-restricted marginal structural models
A new class of Marginal Structural Models (MSMs), History-Restricted MSMs (HRMSMs), was recently introduced for longitudinal data for the purpose of defining causal parameters which may often be better suited for public health research or at least more practicable than…
Using drink size to talk about drinking during pregnancy: Early start plus
Heavy drinking during pregnancy can cause birth defects and other alcohol-related effects. Because costs associated with fetal complications are high, health care organizations are invested in finding ways to intervene with pregnant drinkers. We describe a computerized intervention tested at…
Early start: an integrated model of substance abuse intervention for pregnant women
Untreated perinatal substance abuse is associated with serious adverse maternal and neonatal outcomes. Historically, many barriers have prevented pregnant women from seeking treatment. Early Start (ES) breaks new ground by sidestepping these barriers with a fully integrated service delivery model.ES…
Surgical outcomes in human immunodeficiency virus-infected patients in the era of highly active antiretroviral therapy
HYPOTHESIS: Matched patients who test positive or negative for human immunodeficiency virus (HIV) who are undergoing comparable operations have similar complication rates and outcomes. DESIGN: A retrospective study of surgical outcomes in HIV-infected and matched HIV-noninfected patients. Baseline information including…
Cost-sharing for emergency care and unfavorable clinical events: findings from the safety and financial ramifications of ED copayments study
OBJECTIVE: To evaluate the effect of emergency department (ED) copayment levels on ED use and unfavorable clinical events. Data Source/Study Setting. Kaiser Permanente-Northern California (KPNC), a prepaid integrated delivery system. STUDY DESIGN: In a quasi-experimental longitudinal study with concurrent controls,…
Unstudied infants: outcomes of moderately premature infants in the neonatal intensive care unit
BACKGROUND: Newborns of 30-34 weeks gestation comprise 3.9% of all live births in the United States and 32% of all premature infants. They have been studied much less than very low birthweight infants. OBJECTIVE: To measure in-hospital outcomes and readmission…
Hemoglobin level, chronic kidney disease, and the risks of death and hospitalization in adults with chronic heart failure: the Anemia in Chronic Heart Failure: Outcomes and Resource Utilization (ANCHOR) Study
BACKGROUND: Previous studies have associated reduced hemoglobin levels with increased adverse events in heart failure. It is unclear, however, whether this relation is explained by underlying kidney disease, treatment differences, or associated comorbidity. METHODS AND RESULTS: We examined the associations…
Unintended consequences of caps on Medicare drug benefits
BACKGROUND: Little information exists about the consequences of limits on prescription-drug benefits for Medicare beneficiaries. METHODS: We compared the clinical and economic outcomes in 2003 among 157,275 Medicare+Choice beneficiaries whose annual drug benefits were capped at 1,000 dollars and 41,904…
Hysterectomy rates for benign indications
OBJECTIVE: To investigate the annual rates, types, and indications for hysterectomies performed for benign disease in Kaiser Permanente Northern California from 1994 to 2003. METHODS: All women, 20 years or age or older, who were undergoing hysterectomy for benign indications…
Early experiences with e-health services (1999-2002): promise, reality, and implications
BACKGROUND: E-health services may improve the quality and efficiency of care; however, there is little quantitative data on e-health use. OBJECTIVE: The objective of this study was to examine trends in e-health use and user characteristics. RESEARCH DESIGN: This was…
An observational study examining the impact of capecitabine on warfarin antithrombotic activity and bleeding complications
OBJECTIVE: The objectives of this study are to quantify the frequency of concomitant use of capecitabine and warfarin, and to quantify the rate of bleeding events and elevated international normalized ratio (INR) among concomitant users of warfarin and capecitabine. RESEARCH…
Sex and racial/ethnic disparities in outcomes after acute myocardial infarction: a cohort study among members of a large integrated health care delivery system in northern California
BACKGROUND: Previous studies have documented sex and racial/ethnic disparities in outcomes after acute myocardial infarction (AMI), but the explanation of these disparities remains limited. In a setting that controls for access to medical care, we evaluated whether sex and racial/ethnic…
TPMG Northern California appointments and advice call center
Kaiser Permanente (KP) has been developing its use of call centers as a way to provide an expansive set of healthcare services to KP members efficiently and cost effectively. Since 1995, when The Permanente Medical Group (TPMG) began to consolidate…
Organizational barriers to physician participation in cancer clinical trials
OBJECTIVE: To assess barriers to physician participation in cancer clinical trials among oncologists, oncology leaders, and health plan leaders. STUDY DESIGN: Mail survey of 221 oncologists combined with semistructured telephone interviews with oncology and plan leaders at 10 integrated healthcare…
Menopause, physical activity, and body composition/fat distribution in midlife women
PURPOSE: Hormonal changes associated with menopause, chronological aging, and lifestyle, specifically physical activity, may all influence the changes in body composition and fat distribution experienced by midlife women. This cross-sectional study examined those relations in a representative sample of 248…
Medicaid chemical dependency patients in a commercial health plan: do high medical costs come down over time?
A cohort of 197 Medicaid-insured patients presenting for treatment in Kaiser Permanente's outpatient chemical dependency treatment program were observed the year prior to their program intake visit and followed for 3 years afterwards, to compare their medical costs and utilization…
Use of e-Health services between 1999 and 2002: a growing digital divide
OBJECTIVE: To evaluate the patterns of e-Health use over a four-year period and the characteristics of users. DESIGN: Longitudinal, population-based study (1999-2002) of members of a prepaid integrated delivery system. Available e-Health services included ordering prescription drug refills, scheduling appointments,…
Physical activity and changes in weight and waist circumference in midlife women: findings from the Study of Women’s Health Across the Nation
Controversy exists regarding the extent to which age, menopausal status, and/or lifestyle behaviors account for the increased weight, fat mass, and central adiposity experienced by midlife women. To address this question, the authors longitudinally examined the relations of aging, menopausal…
Can disease management reduce health care costs by improving quality?
Disease management (DM) promises to achieve cost savings by improving the quality of care for chronic diseases. During the past decade the Permanente Medical Group in Northern California has implemented extensive DM programs. Examining quality indicators, utilization, and costs for…
Barriers to hospice care and referrals: survey of physicians’ knowledge, attitudes, and perceptions in a health maintenance organization
INTRODUCTION: Many proponents of hospice care believe that this service is underutilized. OBJECTIVE: To determine physicians' perceptions of hospice utilization and of their own hospice referral pattern; their perceived and actual knowledge of appropriate hospice referral diagnoses; and perceived barriers…
Using chart reviews to assess postpartum substance abuse. A pilot study
The use of chart reviews to assess substance use one-year postpartum was examined in this pilot study by comparing interviews with chart reviews for 23 women assessed positive for risk during pregnancy. There was no indication that providers asked about…
Risk of cesarean delivery in nulliparous women at greater than 41 weeks’ gestational age with an unengaged vertex
OBJECTIVE: The purpose of this study was to determine whether an unengaged vertex significantly increased the risk of cesarean delivery in nulliparous patients at 41 weeks or greater. STUDY DESIGN: The medical records from all nulliparous patients greater than 41…
Outcomes of ostomy procedures in patients aged 70 years and older
HYPOTHESIS: Patients aged 70 years and older undergo proportionately more emergency and permanent fecal ostomy procedures than younger patients. Older patients have comparable short-term outcomes in morbidity and mortality, with adverse outcomes dependent on comorbid conditions and timing of the…
Wine, liquor, beer, and mortality
A substantially increased risk for heavy drinkers and a slightly reduced risk for lighter drinkers results in the J-shaped alcohol-mortality curve. Limited data suggest a more favorable mortality experience for drinkers of wine than for drinkers of liquor or beer.…
The early repolarization normal variant electrocardiogram: correlates and consequences
PURPOSE: We compared the characteristics and outcomes of patients with 'early repolarization' electrocardiograms (ECGs) with those who had normal ECGs. METHODS: In 1983 to 1985, we collected photocopies of 2234 selected ECGs from 73088 patients undergoing health examinations. Excluding 153…
Traits of persons who drink decaffeinated coffee
PURPOSE: Little is known about the traits of decaffeinated coffee drinkers, who are sometimes used to ascertain whether the health effects of coffee intake are due to caffeine or some other coffee ingredient. METHODS: We studied these traits in 12,467…
Reproducibility of increased blood pressure during an emergency department or urgent care visit
STUDY OBJECTIVE: We determine the reproducibility of increased blood pressure measurements among adults in the emergency department or minor injury clinic. METHODS: The study was conducted at Kaiser Permanente Medical Center in Hayward, CA, a large, group-model health maintenance organization…
A cohort study of the incidence of serious acute liver injury in diabetic patients treated with hypoglycemic agents
BACKGROUND: The incidence of acute liver failure or serious liver injury in diabetic patients is needed to evaluate the safety of hypoglycemic drug therapy. METHODS: We conducted a retrospective cohort study of 5 health maintenance organizations. Study patients were 171,264…
Perinatal substance abuse intervention in obstetric clinics decreases adverse neonatal outcomes
OBJECTIVE: To evaluate the effect of Early Start, a managed care organization's obstetric clinic-based perinatal substance abuse treatment program, on neonatal outcomes. STUDY DESIGN: Study subjects were 6774 female Kaiser Permanente members who delivered babies between July 1, 1995 and…
Physical activity and menstrual cycle characteristics in two prospective cohorts
Relations between physical activity and prospectively collected menstrual cycle characteristics were examined in two large cohorts. One cohort consisted of women employed in the semiconductor industry in 1989 who participated in a prospective study of reproductive outcomes (n = 367).…
Life after a ventricular arrhythmia
BACKGROUND: There are few data from community-based evaluations of outcomes after a life-threatening ventricular arrhythmia (LTVA). We evaluated patients' quality of life (QOL) and medical costs after hospitalization and treatment for their first episode of an LTVA. METHODS: We prospectively…
Health-related quality of life and future health care utilization for asthma
BACKGROUND: Although health-related quality of life (HRQL) has been increasingly used as an outcome in asthma, its utility for identifying patients at risk for adverse asthma outcomes has not been established. OBJECTIVE: In a prospective cohort study, to evaluate the…
Foot problems as risk factors of fractures
This case-control study examines whether foot problems are risk factors of fractures of five sites among people aged 45 years or older at six Kaiser Permanente Medical Centers in northern California. From October 1996 to May 2001, interviewers collected information…
Treatment decisions about lumbar herniated disk in a shared decision-making program
BACKGROUND: An explicit process of collaborative (shared) decision making involving the patient and physician has been recommended for discretionary surgical procedures in which small-area analysis demonstrates high variation not attributable to differences in the patient population in the area. One…
Different slopes for different folks: socioeconomic and racial/ethnic disparities in asthma and hay fever among 173,859 U.S. men and women
Although allergic diseases such as asthma and hay fever are a major cause of morbidity in industrialized countries, most studies have focused on patterns of prevalence among children and adolescents, with relatively few studies on variations in prevalence by race/ethnicity…
A multimedia breast cancer education intervention for low-income Latinas
This paper discusses the results from the field test of a multimedia health education intervention, designed to provide breast cancer education for low income Latinas. The purpose of the field test was to ascertain whether the intervention produced significant changes…
Rehospitalization for neonatal dehydration: a nested case-control study
OBJECTIVES: To determine the incidence of neonatal dehydration leading to rehospitalization, whether clinical and health services data could predict its occurrence, and the outcome of dehydrated infants. METHODS: We employed a retrospective case-control design nested within a cohort of 51…
Medicaid patients in a private health maintenance organization: patterns of chemical dependency treatment
Although many Medicaid beneficiaries receive health care through commercial health maintenance organizations (HMOs), the impact of private managed care on low-income individuals seeking treatment for substance abuse has rarely been studied. This study examined treatment patterns of 234 Medicaid recipients…
Utilization of health services among patients referred to an alcohol treatment program
This study assessed utilization of health services among 1,317 adults referred to an outpatient Psychiatry Department alcohol treatment program from July, 1988 through December, 1989. The mean number of visits/year for 1 year before and 4 years after treatment referral…
Safety of neonatal hepatitis B vaccine administration
OBJECTIVE: To determine whether hepatitis B vaccination of newborns increases the incidence of fever and/or suspected sepsis. METHODS: A prospective clinical study was undertaken at the Kaiser Permanente San Francisco Medical Center involving normal full term newborns born between November…
The prevalence of clinically recognized obsessive-compulsive disorder in a large health maintenance organization
OBJECTIVE: Little is known about the prevalence of obsessive-compulsive disorder (OCD) as recognized in clinical settings. The authors report data on the prevalence of clinically recognized OCD in a large, integrated, group practice health maintenance organization (HMO). METHOD: The authors…
Correlates of breast cancer screening among low-income, low-education Latinas
INTRODUCTION: This paper discusses the factors associated with breast cancer screening among low-education, low-income Latinas. BACKGROUND: These data were collected as part of a breast cancer educational intervention study aimed at this population. The objective of the larger study was…
Comparison of quality and cost-effectiveness in the evaluation of symptomatic cholelithiasis with different approaches to ultrasound availability in the ED
Ultrasound is the imaging study of choice for the detection of gallstones, but ultrasound through medical imaging departments (MI Sono) is not readily available on an immediate basis in many emergency departments (EDs). Several studies have shown that emergency physicians…
Patterns of cigarette smoking and alcohol use among lesbians and bisexual women enrolled in a large health maintenance organization
OBJECTIVES: This study compared the prevalence of cigarette smoking and alcohol use among lesbians and bisexual women with that among heterosexual women. METHODS: Logistic regression models were created with data from an extensive member health survey at a large health…
Impact of the change in polio vaccination schedule on immunization coverage rates: a study in two large health maintenance organizations
OBJECTIVE: In January 1997, one of the most significant changes to United States vaccine policy occurred when polio immunization guidelines changed to recommend a schedule containing inactivated polio vaccine (IPV). There were concerns that parent or physician reluctance to accept…
Targeted testing of children for tuberculosis: validation of a risk assessment questionnaire
OBJECTIVE: Given the directive of the American Academy of Pediatrics to test children for tuberculosis (TB) only if they are at high risk for the disease, we sought to determine how well a risk assessment questionnaire can predict a positive…
Slow infusion for the prevention of akathisia induced by prochlorperazine: a randomized controlled trial
The utility of intravenous prochlorperazine (PCZ) in the treatment of nausea, vomiting, and headache may be limited by the akathisia that occurs frequently with the recommended 2-min infusion rate. We tested the hypothesis that decreasing the rate of PCZ infusion…
Do surrogate decision makers provide accurate consent for intensive care research?
CONTEXT: ICU patients are often rendered incapable of making decisions as a result of their illness. The accuracy with which patients' surrogates consent to research on their behalf is not known. OBJECTIVE: To determine if surrogate decision makers provide accurate…
Early Start: an obstetric clinic-based, perinatal substance abuse intervention program
Maternal substance abuse is a serious problem with significant adverse effects to mothers, fetuses, and children. The Early Start Program provides pregnant women in a managed care organization with screening and early identification of substance abuse problems, early intervention, ongoing…
Hormone replacement therapy and the risk of myocardial infarction in women with coronary risk factors
To assess the risk of myocardial infarction in users of post-menopausal hormone replacement therapy who are at high risk of coronary disease because of hypertension, diabetes mellitus, or smoking, we used data from a previously published case-control study of women…
Efficacy of nurse telehealth care and peer support in augmenting treatment of depression in primary care
BACKGROUND: Primary care treatment of depression needs improvement. OBJECTIVE: To evaluate the efficacy of 2 augmentations to antidepressant drug treatment. DESIGN: Randomized trial comparing usual care, telehealth care, and telehealth care plus peer support; assessments were conducted at baseline, 6…
Ultrasound availability in the evaluation of ectopic pregnancy in the ED: comparison of quality and cost-effectiveness with different approaches
The liberal use of ultrasonography has been advocated in patients with first trimester cramping or bleeding to avoid misdiagnosis of ectopic pregnancy in the emergency department (ED). The cost-effectiveness of different approaches to ultrasound availability has not been previously reported.…
Risk of pulmonary embolism and/or deep venous thrombosis in Asian-Americans
Several reports from Asian countries suggest a low prevalence of pulmonary embolism (PE) and deep venous thrombosis (DVT) in Asians, and sparse US data show that a slightly higher prevalence of PE/DVT in 'nonwhites' than in whites is evident in…
Neonatal assisted ventilation: predictors, frequency, and duration in a mature managed care organization
OBJECTIVES: Reference data are lacking on the frequency and duration of assisted ventilation in neonates. This information is essential for determining resource needs and planning clinical trials. As mortality becomes uncommon, ventilator utilization is increasingly used as a measure for…
Efficacy, safety and immunogenicity of heptavalent pneumococcal conjugate vaccine in children. Northern California Kaiser Permanente Vaccine Study Center Group
OBJECTIVE: To determine the efficacy, safety and immunogenicity of the heptavalent CRM197 pneumococcal conjugate vaccine against invasive disease caused by vaccine serotypes and to determine the effectiveness of this vaccine against clinical episodes of otitis media. METHODS: The Wyeth Lederle…
The cost of health conditions in a health maintenance organization
In this retrospective cohort analysis of all adults who were members of Kaiser Permanente, Northern California, between July 1995 and June 1996 (N = 2,076,303), the authors estimated the prevalence, average annual costs per person, and percentage of total direct…
Parents’ preferences for outcomes associated with childhood vaccinations
BACKGROUND: The number of shots in the childhood immunization schedule has been increasing and is likely to continue to increase in the coming years. Consideration of the psychologic costs of multiple injections, adverse events and vaccine-preventable disease is therefore growing…
Cost of care for patients in cancer clinical trials
BACKGROUND: Information on the costs of medical care for patients enrolled in clinical trials is needed by policymakers evaluating ways to facilitate clinical research in a managed care environment. We examined the direct costs of medical care for patients enrolled…
Spousal concordance for cancer incidence: A cohort study
BACKGROUND: Because married couples share at least their home environment, spousal aggregation of cancer might provide clues to unsuspected etiologic factors. The authors sought to measure the concordance of cancer occurrence in married couples and explore factors that might explain…
Frequency of neonatal bilirubin testing and hyperbilirubinemia in a large health maintenance organization
OBJECTIVE: To determine the frequency and interhospital variation of bilirubin testing and identified hyperbilirubinemia in a large health maintenance organization. DESIGN: Retrospective cohort study. SETTING: Eleven Northern California Kaiser Permanente hospitals. SUBJECTS: A total of 51,387 infants born in 1995-1996…
Rehospitalization for respiratory syncytial virus among premature infants
OBJECTIVES: New interventions to prevent respiratory syncytial virus (RSV) have recently become available. Clinical decisions about the use of these interventions require a better understanding of the incidence of and risk factors for RSV. We sought to characterize the epidemiology…
Relationship of the facial nerve to the tympanic annulus: a direct anatomic examination
OBJECTIVE: To examine the relation of the facial nerve to the only identifiable surgical landmark in the external auditory canal. INSTITUTION: Community-based teaching hospital. STUDY DESIGN: Examination of formalin-fixed human temporal bones. BACKGROUND: The transcanal approach is often used in…
Resolving the gatekeeper conundrum: what patients value in primary care and referrals to specialists
CONTEXT: Few data are available regarding how patients view the role of primary care physicians as 'gatekeepers' in managed care systems. OBJECTIVE: To determine the extent to which patients value the role of their primary care physicians as first-contact care…
Rehospitalization in the first two weeks after discharge from the neonatal intensive care unit
BACKGROUND: High-risk newborns are known to have higher than average utilization of services after discharge from the neonatal intensive care unit (NICU). Most studies on this subject report aggregate data over periods ranging from 1 to 3 years postdischarge. Little…
Quality of primary care practice in a large HMO according to physician specialty
OBJECTIVE: To determine whether physician specialty was associated with differences in the quality of primary care practice and patient satisfaction in a large, group model HMO. DATA SOURCES/STUDY SETTING: 10,608 patients ages 35-85 years, selected using stratified probability sampling from…
Computer-based models to identify high-risk adults with asthma: is the glass half empty of half full?
This study developed and evaluated the performance of prediction models for asthma-related adverse outcomes based on the computerized hospital, clinic, and pharmacy utilization databases of a large health maintenance organization. Prediction models identified patients at three- to four-fold increased risk…
Predicting advanced proximal colonic neoplasia with screening sigmoidoscopy
CONTEXT: Indications are not well defined for follow-up colonoscopy for all patients with distal colonic tubular adenomas (TAs) found at screening sigmoidoscopy. OBJECTIVE: To determine whether distal adenoma size, number, and villous histology, along with family history and age, are…
Physical activity patterns in a diverse population of women
BACKGROUND: Demographic and psychosocial correlates of activity in domains other than recreational activity have not been well characterized and may be particularly relevant for health promotion efforts aimed at women. METHODS: Cross-sectional relationships between recreational, occupational, and household/caregiving physical activity…
Habitual physical activity and menopausal symptoms: a case-control study
A case-control study design was used to examine whether habitual physical activity prior to the final menstrual period (FMP) was associated with reduced risk of vasomotor and other symptoms during the perimenopausal period. Both cases and controls were identified through…
Alcohol consumption and utilization of health services in a health maintenance organization
OBJECTIVES: This study examined the relation between alcohol use and utilization of health services during a 3-year period in a sample of 4,264 adult respondents to a member health survey in a health maintenance organization. METHODS: Respondents were categorized as…
Structured review of neonatal deaths in a managed care organisation
We sought to quantify neonatal mortality (< 28 days) in a 10-hospital system, determine what proportion was associated with suboptimal neonatal care and make recommendations on how neonatal mortality rates (NMRs) could be used in quality improvement efforts. Deaths were…
Neonatal group B streptococcal infection in a managed care population. Perinatal Group B Streptococcal Infection Study Group
OBJECTIVE: In a health maintenance organization population, we determined the incidence of early-onset (at less than or equal to 7 days) neonatal group B streptococcal (GBS) disease, the sensitivity and prevalence of labor risk factors, the adherence to a protocol…
Experience with a managed care approach to HIV infection: effectiveness of an interdisciplinary team
To evaluate the function and effectiveness of a multidisciplinary team for managing human immunodeficiency virus (HIV) infection, we conducted a follow-up cohort study of HIV-positive patients managed according to a clinical care path at a staff-based health maintenance organization (HMO).…
Computer-based models to identify high-risk children with asthma
Effective management of populations with asthma requires methods for identifying patients at high risk for adverse outcomes. The aim of this study was to develop and validate prediction models that used computerized utilization data from a large health-maintenance organization (HMO)…
Obesity, health services use, and health care costs among members of a health maintenance organization
BACKGROUND: Obesity is an independent risk factor for a variety of chronic diseases and is therefore a potential source of avoidable excess health care expenditures. Previous studies of obesity and health care costs have used group level data, applying estimates…
Developmentally supportive care in a neonatal intensive care unit: a research utilization project
PURPOSE: To implement three aspects of developmental care: lower noise levels, decreased light levels, and flexed, midline positioning. DESIGN: Research utilization project. The developmental care interventions were implemented on a daily basis for two hours of 'quiet time' during each…
Monitoring women at risk for preterm labor
BACKGROUND: Preterm birth is a major cause of perinatal morbidity and mortality. Whether the rate of preterm birth can be reduced by frequent contact between nurses and pregnant women or home monitoring of uterine activity is not known. METHODS: We…
Cataract extraction. Risk factors in a health maintenance organization population under 60 years of age
Risk factors for cataract extraction in a young (less than 60 years of age) urban health maintenance organization population were evaluated in a case-control study. The subjects (72 case-control pairs) subscribed to the Kaiser Permanente Medical Care Program in the…
Precursors of essential hypertension: body weight, alcohol and salt use, and parental history of hypertension
Body mass index, alcohol and salt consumption, and parental history of hypertension were examined as possible predictors of the development of essential hypertension in 1,031 persons, ages 30-49 years at entry, with documented normotension followed by documented hypertension after a…
Cholecystectomy and large bowel cancer
The records of 5898 patients with colorectal cancer and 27,687 controls were examined for previous cholecystectomy. The estimated relative risks (and 95% confidence intervals) of development of any cancer of the large bowel and cancer of the right colon after…
Serum retinol and retinol-binding protein levels do not predict subsequent lung cancer
Retinol and retinol-binding protein levels were measured in sera previously obtained, and stored in the frozen state, at multiphasic health checkups from 151 persons subsequently found to have lung cancer (cases) and 302 persons who remained free of cancer (controls).…
Multiphasic Health Checkup Evaluation: a 16-year follow-up
The Multiphasic Health Checkup Evaluation Study, a long-term clinical trial, has been completed. A study group of 5156 men and women age 35-54 at entry was urged to have annual multiphasic health checkups (MHCs) for 16 years. A control group…
Psychological questionnaire score, cigarette smoking, and myocardial infarction: a continuing enigma
The ability of a group of 94 psychological questions to discriminate between men in whom cigarette smoking was associated with increased risk of myocardial infarction and men in whom smoking was not so associated remains puzzling. Further analyses, controlling for…