Prevalence, treatment, and control of hypertension among African Americans and Caucasians at primary care sites for medically under-served patients

Abstract

Hypertension is a major contributor to ethnic disparities in cardiovascular disease, especially among low-income African Americans in the southeast United States. To assess differences between African Americans and Caucasians in the prevalence, treatment, and control of hypertension in outpatient clinics for under-served patients in South Carolina. A random sample of outpatient charts on 7795 adults was abstracted from 31 primary care clinics providing health care for approximately 180,000 medically under-served patients. Variables included visit dates, blood pressures (BP), diagnosis of hypertension, and medications. Data were abstracted from outpatient medical records on 4694 African Americans (1483 men, 3195 women, 16 gender unknown, age 46.8 +/- 0.3 years) and 2540 Caucasians (1031 men, 1492 women, 17 gender unknown, age 47.7 +/- 0.4 years). The prevalence of hypertension was greater in African Americans than Caucasians (47.6% vs 31.0%, P < .001). The percentages of hypertensive African Americans and Caucasians receiving BP medications were similar (83.4% vs 81.6%, P=NS). Although African-American hypertensives were more likely than Caucasian hypertensives to receive diuretics and calcium channel blockers and less likely to receive beta-blockers, the number of BP medications was similar for both groups (1.44 +/- 0.02 vs 1.40 +/- 0.04, P=NS). Despite comparable treatment, African Americans were less likely than Caucasians to have BP controlled to <140/90 mm Hg at the most recent clinic visit (40.9% vs 46.3%, P=.01). In healthcare settings for medically under-served patients, the greater prevalence and lesser control of hypertension, despite similar treatment intensity, may contribute to higher rates of cardiovascular disease among African Americans than Caucasians.