Authors' objectives:

Hypertension affects more than 50 million people in the United States alone. Despite clear evidence regarding the beneficial effects of quality treatment for high blood pressure, many millions of diagnosed and undiagnosed hypertensives are not receiving the optimal standard of care. The difference in patient outcomes achieved with present hypertension treatment methods and those thought to be possible using best practice treatment methods is known as a quality gap, and such gaps are at least partly responsible for the loss of thousands of lives each year. This review was organized to bring a systematic assessment of different quality improvement (QI) strategies and their effects to the process of identifying and managing hypertension.

Authors' results and conclusions: Sixty-three articles reporting a total of 82 comparisons met the inclusion criteria. Studies of hypertension identification were found to be too heterogeneous for quantitative analysis. The majority of screening studies were clinic-based (with a few offered at work sites), and the most common strategies involved patient and/or provider reminders. These generally showed positive results; several studies found that patients were more likely to know their blood pressure or attend clinic visits after receiving reminders. Across all studies with a variety of strategies, the median reductions in systolic blood pressure (SBP) and diastolic blood pressure (DBP) were 4.5 mmHg (interquartile range: 1.5, 11.0) and 2.1 mmHg (interquartile range: -0.2, 5.0), respectively. The median increase in the proportion of patients in the target SBP range and target DBP range was 16.2 percent (interquartile range: 10.3, 32.2), and 6.0 percent (interquartile range: 1.5, 17.5), respectively. Studies that focused on improving provider adherence showed a range of median reduction of 1.3 percent to a median improvement of 3.3 percent across all QI strategies. Overall, patient adherence showed a median improvement of 2.8 percent (interquartile range: 1.9, 3.0).

Authors' recommendations: Our review found that QI strategies result in increased detection of hypertension, and improved management, as measured by blood pressure. However, we found only small changes in provider and patient adherence due to QI interventions. Studies that included organizational change and patient education reported greater improvements in blood pressure control than did studies without these strategies, but the evidence is not sufficient to definitively establish the superiority of any individual QI strategy relative to others. The reported improvements in blood pressure control were smaller in larger studies than in smaller studies, raising a concern that our overall measures of the effectiveness of QI strategies may be overestimated because of publication bias. Closing the quality gap will take sustained effort from the many parties with an interest in detection and management of hypertension. Our review documents the varied approaches to QI for hypertension that have received careful evaluation. The summary analyses provide a high level overview of these QI interventions. Perhaps as importantly, the details of individual studies offer a resource that may help guide further QI implementation and evaluation. Despite the many studies documented here, the evidence about the usefulness of QI strategies in hypertension care is incomplete. There is a strong need for further and more detailed evaluation. Future studies will be more useful if they are designed rigorously, describe QI interventions carefully, and provide information about the organizational setting in which they are performed. Each new attempt to close the quality gap in hypertension will likely need to be tailored to specific circumstances.42 We hope this report provides a useful starting point for individuals and organizations that are trying to improve the detection and management of hypertension, and for investigators attempting to further the field of quality improvement.

Authors' methods: Systematic review

Project Status: Completed

URL for project: http://www.ahrq.gov/clinic/tp/hypergap3tp.htm

Year Published: 2005

English language abstract: An English language summary is available

Publication Type: Not Assigned

Country: United States

Organisation Name: Agency for Healthcare Research and Quality

Contact Address: Center for Outcomes and Evidence Technology Assessment Program, 540 Gaither Road, Rockville, MD 20850, USA. Tel: +1 301 427 1610; Fax: +1 301 427 1639;

Contact Name: martin.erlichman@ahrq.hhs.gov

Contact Email: martin.erlichman@ahrq.hhs.gov

Copyright: Agency for Healthcare Research and Quality (AHRQ)