Trends in Prevalence, Awareness, Treatment, and Control of Hypertension in the United States, 1988-2000

Abstract

CONTEXT: Prior analyses of National Health and Nutrition Examination Survey (NHANES) data through 1991 have suggested that hypertension prevalence is declining, but more recent self-reported rates of hypertension suggest that the rate is increasing. OBJECTIVE: To describe trends in the prevalence, awareness, treatment, and control of hypertension in the United States using NHANES data. DESIGN, SETTING, AND PARTICIPANTS: Survey using a stratified multistage probability sample of the civilian noninstitutionalized population. The most recent NHANES survey, conducted in 1999-2000 (n = 5448), was compared with the 2 phases of NHANES III conducted in 1988-1991 (n = 9901) and 1991-1994 (n = 9717). Individuals aged 18 years or older were included in this analysis. MAIN OUTCOME MEASURES: Hypertension, defined as a measured blood pressure of 140/90 mm Hg or greater or reported use of antihypertensive medications. Hypertension awareness and treatment were assessed with standardized questions. Hypertension control was defined as treatment with antihypertensive medication and a measured blood pressure of less than 140/90 mm Hg. RESULTS: In 1999-2000, 28.7% of NHANES participants had hypertension, an increase of 3.7% (95% confidence interval [CI], 0%-8.3%) from 1988-1991. Hypertension prevalence was highest in non-Hispanic blacks (33.5%), increased with age (65.4% among those aged > or =60 years), and tended to be higher in women (30.1%). In a multiple regression analysis, increasing age, increasing body mass index, and non-Hispanic black race/ethnicity were independently associated with increased rates of hypertension. Overall, in 1999-2000, 68.9% were aware of their hypertension (nonsignificant decline of -0.3%; 95% CI, -4.2% to 3.6%), 58.4% were treated (increase of 6.0%; 95% CI, 1.2%-10.8%), and hypertension was controlled in 31.0% (increase of 6.4%; 95% CI, 1.6%-11.2%). Women, Mexican Americans, and those aged 60 years or older had significantly lower rates of control compared with men, younger individuals, and non-Hispanic whites. CONCLUSIONS: Contrary to earlier reports, hypertension prevalence is increasing in the United States. Hypertension control rates, although improving, continue to be low. Programs targeting hypertension prevention and treatment are of utmost importance.