What is the prevalence of resistant hypertension in the United States?

PURPOSE OF REVIEW: Resistant hypertension, defined as blood pressure uncontrolled on three, or controlled with at least four, antihypertensive agents (including a diuretic), is associated with higher risk of secondary hypertension, cardiovascular and renal events, and increased healthcare expenditures. Until recently, however, the prevalence of resistant hypertension in the United States (US) was based on clinical trial registries or pharmacy databases. RECENT FINDINGS: Recent analyses of National Health and Nutrition Examination Survey (NHANES) data, drawn from representative samples of the adult, noninstitutionalized, civilian population, have estimated the prevalence of resistant hypertension at 8.9 ± 0.6% of the US hypertensive population in 2003-2008. A time-sequence comparison of NHANES data from 1998 through 2008 suggests that, unlike hypertension, resistant hypertension is becoming more prevalent (e.g., 20.7% in 2005-2008), due to aging and increased obesity in the general population. Resistant hypertension was more frequent in people who were older, obese, male, African American or nonblack Hispanic. SUMMARY: In coming years, even if the prevalence of hypertension remains stable, resistant hypertension is likely to increase, especially as the proportion of treated hypertension increases. Because of increased use of healthcare resources, resistant hypertensive patients should be identified early, and greater efforts made to control their blood pressures.