Kaiser Permanente Northern California nearly doubled the rate of blood pressure control among adult members with diagnosed hypertension between 2001 and 2009 through one of the largest, community-based hypertension programs nationally, as reported today in the Journal of the American Medical Association.
Using the Healthcare Effectiveness Data and Information Set (HEDIS) quality measurement set by the National Committee for Quality Assurance (NQCA), the rate of hypertension control increased from 43.6 percent to 80.4 percent throughout Kaiser Permanente Northern California between 2001 and 2009.
In contrast, the national mean control rate increased from 55.4 percent to 64.1 percent during that period. California-wide control rates, available since 2006, were similar but slightly higher than the national average — 63.4 percent versus 69.4 percent from 2006 to 2009.
“This is the first successful, large-scale program sustained over a long period of time,” said lead author Marc G. Jaffe, MD, an endocrinologist and clinical leader of the Kaiser Permanente Northern California Cardiovascular Risk Reduction Program. “Following the study period, our hypertension control rates have continued to improve from nearly 84 percent in 2010 to 87 percent in 2011. This has huge implications for the health of our members because this success translates into reduced risk of stroke and heart disease.”
Hypertension affects 65 million adults in the United States, 29 percent of Americans age 18 years or older, and is a major contributor to cardiovascular disease. Blood pressure control remains elusive nationally despite widespread availability of effective therapies, and limited data exist about the implementation and results of large, sustained hypertension programs.
The Kaiser Permanente Northern California (KPNC) Hypertension program was introduced system-wide in 2001 as a multi-faceted approach to blood pressure control and quality improvement. The five key components of the program include a comprehensive hypertension patient registry, quality performance metrics with dissemination of successful practices, evidence-based practice guidelines, single pill combination therapy, and medical assistant visits for blood pressure measurement.
System-wide hypertension registry
The registry identified patients with hypertension using outpatient diagnostic codes, pharmacy data and hospitalization records from health plan databases. Between 2001 and 2009, the hypertension registry increased from 349,937 or 15.4 percent of adult membership to 652,763 or 27.5 percent of adult membership. Throughout the study period, the majority of patients were aged 45 to 85 years, and more than half of registry members were women.
“The great value of a comprehensive, updated hypertension registry is that it allows us to identify patient subgroups that have poorly controlled hypertension,” explained senior author Alan S. Go, MD, section chief of Cardiovascular and Metabolic Conditions at the Kaiser Permanente Division of Research. “These patients are then evaluated for appropriateness for treatment intensification. This is consistent with previous studies that have found the most effective intervention to improve blood pressure control in primary care settings is an organized system of regular population review rather than relying primarily on patient- or clinician-focused interventions.”
Hypertension control rates/Quality performance metrics
In 2001, internal hypertension control reports were developed for quality improvement use. Control was defined using NCQA HEDIS measures as systolic blood pressure less than 140 mmHg and systolic blood pressure less than 90 mmHg (equal to or less than 140/90 mmHg before 2006). Frequent hypertension control quality reports identified high-performing medical centers where successful practices or innovations were identified and then disseminated system-wide. Although individual clinician feedback has long been used to promote change, the focus on clinic-level feedback facilitated operational and system-level change.
Evidence-based practice guidelines
In 2001, an evidence-based, four-step hypertension control algorithm was developed to aid clinicians. The guideline was updated every two years based on emerging randomized trial evidence and national guidelines. System-wide adoption, evaluation and distribution of an evidence-based practice guideline that had timely incorporation of new evidence facilitated the ability to introduce new treatment options and to re-emphasize existing evidence-based recommendations.
Single pill combination (SPC) therapy
In 2005, single pill combination (SPC) therapy with lisinopril-hydrochlorothiazide was incorporated into the regional clinical practice guideline with subsequent rapid uptake system-wide. SPC therapy was recommended in the hypertension guideline as an option for initial antihypertensive treatment and when two antihypertensive medications were required. Researchers noted that single pill combinations have important advantages including improved adherence, lower patient cost, and improved blood pressure control.
Medical assistant visits for follow-up measurements
In 2007, all medical centers developed a medical assistant follow-up visit typically scheduled two to four weeks after a medication adjustment. A medical assistant measured blood pressure and informed the primary care physician, who then directed treatment decisions and follow-up planning. This system accelerated treatment intensification without significantly increasing the need for repeat clinician visits while simultaneously improving patient convenience and affordability.
“The program supports the evidence for an organized, comprehensive system of regular population review and intervention to improve blood pressure control in primary care settings,” said Jaffe. “More importantly, if taken to scale, it has tremendous potential to improve the health of millions. High blood pressure is an important modifiable risk factor for life-threatening illnesses including heart disease, stroke, and kidney disease.As the population ages, high blood pressure will become an even bigger problem unless we act now.”
Additional authors on the study include A. Lee, MD, of the Department of Endocrinology, Kaiser Permanente South San Francisco Medical Center; Joseph D. Young, MD, of the Department of Medicine, Kaiser Permanente Oakland Medical Center; and Stephen Sidney, MD, MPH, of the Division of Research, Kaiser Permanente Northern California, Oakland.