High blood pressure and cardiovascular disease mortality risk among US adults: The Third National Health and Nutrition Examination Survey mortality follow-up study

PURPOSE: We sought to examine whether prehypertension is associated with increased cardiovascular disease (CVD) mortality risk and whether the association of blood pressure with CVD outcome is modified by social demographics or hypertension treatment and control. METHODS: Data from the Third National Health and Nutrition Examination Survey and mortality follow-up through 2000 were used to estimate the relative risk of death from CVD associated with hypertension and prehypertension, after adjusting for confounding and modifying factors. RESULTS: Compared with normotension, the relative risks of CVD mortality were 1.23 (95% confidence interval [95% CI] 0.85-1.79, P = 0.26) for prehypertension, 1.64 (95% CI 1.11-2.41, P = 0.01) for hypertension, 1.74 (95% CI 1.28-2.49, P = 0.007) for uncontrolled hypertension, and 1.15 (95% CI 0.79-1.80, p = 0.53) for controlled hypertension. Hypertensive adults < 65 years and non-Hispanic blacks had a 3.86-fold and a 4.65-fold increased CVD mortality risk respectively. Age, gender, and race/ethnicity stratified analyses showed no associations between prehypertension and CVD mortality. However, blood pressure at a high range of prehypertension (130-139/84-89 mmHg) was associated with increased risk of CVD mortality (hazard ratio 1.41, P < 0.05) relative to blood pressure less than 120/80 mmHg. CONCLUSIONS: This study supports a strong, significant, and independent association of elevated blood pressure with CVD mortality risk. Hypertension continued to greatly increase CVD morality risk, particularly among persons < 65 years and non-Hispanic blacks. Treatment and control of hypertension eliminated the excess CVD mortality risk observed among the hypertension population.