Review and special articleScreening for high blood pressure: A review of the evidence for the U.S. Preventive Services Task Force
Introduction
I n the United States, hypertension is responsible for 35% of all cardiovascular events (myocardial infarction and stroke), 49% of all episodes of heart failure, and 24% of all premature deaths.1 Patients with hypertension have 2 to 4 times more risk for stroke, myocardial infarction, heart failure, and peripheral vascular disease than patients without hypertension.2 Additionally, they have an increased risk for end-stage renal disease, retinopathy, and aortic aneurysm.1, 3, 4 This substantial burden of suffering from hypertension, in combination with a feasible and accurate means of detection, and a clear benefit from treatment,5 have led to a widespread recommendation for screening for hypertension.
In 1996, the U.S. Preventive Services Task Force (USPSTF) reviewed the evidence regarding screening for hypertension.5 Based on that review, the USPSTF strongly recommended screening adults aged 21 years and older using standard office sphygmomanometry. Although the USPSTF did not recommend a specific interval for screening, they noted that measurement every 2 years for patients with previously normal blood pressures and every year in people with borderline levels may be prudent.
In this report, newer evidence relevant to screening for hypertension in adults has been systematically examined to assist the USPSTF in updating its recommendations and the Guide to Clinical Preventive Services.5
Section snippets
Analytic framework and key questions
To examine the role of outpatient clinical screening for hypertension in adults, an analytic framework depicting key questions of interest to the USPSTF was developed (Figure 1). The arrows in the analytic framework represent steps in the chain of logic connecting screening with defined outcomes: cardiovascular disease (CVD), renal failure, and reduction of mortality.
Four key questions guided the literature searches and synthesis of the evidence:
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Key Question No. 1: Does screening and early
Key question 1: does screening for hypertension reduce cardiovascular disease and mortality?
RCTs of screening (versus no screening) would provide the best evidence about the effects of screening for hypertension on CVD and mortality. No such studies were identified. Many trials of hypertension treatment that compared pharmacologic and behavioral intervention to usual care, however, showed a beneficial effect of treatment in patients who were enrolled on the basis of elevated blood pressures detected on screening examinations. These findings suggest that screening may be beneficial,
Discussion
Strong indirect evidence supports screening adults for hypertension. Hypertension is an important contributor to CVD morbidity and mortality. It is predictive of CVD events and reliably detected through screening blood pressure measurements using a standard arm blood pressure cuff and sphygmomanometer. Additionally, treatment of adult hypertensive patients with drug therapy and possibly nonpharmacologic interventions can reduce blood pressure and the incidence of cardiovascular events,
Acknowledgements
This study was developed by the RTI International–University of North Carolina at Chapel Hill (RTI-UNC) Evidence-Based Practice Center under contract to the Agency for Healthcare Research and Quality (AHRQ) (contract # 290-97-0011), Rockville MD. We acknowledge at AHRQ the continuing support of David Atkins, MD, MPH, Chief Medical Officer of the AHRQ Center for Practice and Technology Assessment; and Jean Slutsky, PA, MSPH, Task Order Officer for the USPSTF project.
We are also indebted to our
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