Implementation of a large-scale hypertension program that included evidence-based guidelines and development and sharing of performance metrics was associated with a near-doubling of hypertension control between 2001 and 2009, compared to only modest improvements in state and national control rates, according to a study in the Aug. 21 issue of JAMA.

Marc G. Jaffe, MD, of the Kaiser Permanente South San Francisco Medical Center, South San Francisco, Calif., and colleagues conducted a study to examine the results of a hypertension program in Northern California and to compare rates of hypertension control in that program with statewide and national estimates. The Kaiser Permanente Northern California (KPNC) hypertension program included a multifaceted approach to blood pressure control. Key elements of the program include establishment of a comprehensive hypertension registry, development and sharing of performance metrics, evidence-based guidelines, medical assistant visits for blood pressure measurement, and single-pill combination pharmacotherapy. Patients identified as having hypertension within an integrated health care delivery system in Northern California from 2001-2009 were included.

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The comparison group comprised insured patients in California between 2006-2009 who were included in the Healthcare Effectiveness Data and Information Set (HEDIS) commercial measurement by California health insurance plans participating in the National Committee for Quality Assurance (NCQA) quality measure reporting process. A secondary comparison group was included to obtain the reported national average NCQA HEDIS commercial rates of hypertension control between 2001-2009 from health plans that participated in the NCQA HEDIS quality measure reporting process.

Between 2001 and 2009, the KPNC hypertension registry increased from 349,937 to 652,763. Among hypertension registry members, the average age was 63 years. More than half of registry members were women, and the proportion was similar across study years.

The researchers found that the NCQA HEDIS commercial hypertension control rate within KPNC increased after implementation of the hypertension program from 43.6% in 2001 to 80.4 percent in 2009. "In contrast, the national mean NCQA HEDIS control rate increased from 55.4% to 64.1% between 2001 and 2009. California-wide control rates were available since 2006 and were similar but slightly higher than the national average (63.4% vs. 69.4% from 2006 to 2009)," the authors write.

Following the study period, the NCQA HEDIS hypertension control rate within KPNC continued to improve, from 83.7% in 2010 to 87.1% in 2011.

The authors also found that the rate of lisinopril-hydrochlorothiazide single-pill combination (SPC) prescriptions in KPNC increased from 13 to 23,144 prescriptions per month from 2001 to 2009. During this period, the percentage of angiotensin-converting enzyme (ACE) inhibitor prescriptions dispensed as an SPC (in combination with a thiazide diuretic) increased from less than 1 percent to 27.2%

"In summary, implementation of a large-scale hypertension program was associated with improvements in hypertension control rates between 2001 and 2009," the researchers conclude.