Abstract P316: Prehypertension and Incident Acute Coronary Heart Disease in the REasons for Geographic and Racial Differences in Stroke (REGARDS) Study

Abstract

Objective: The independent prognostic value of prehypertension (preHTN) for incident coronary heart disease (CHD) remains unsettled. Using the REasons for Geographic And Racial Differences in Stroke (REGARDS) cohort study, we examined associations between preHTN and incident acute CHD and CVD death. Methods: REGARDS includes 30,239 black and white community-dwelling adults age 45 and older at baseline. Recruitment occurred from 2003-7, with baseline interviews and in-home data collection for physiologic measures. Follow-up is conducted by telephone every 6 months to detect events and deaths, which are adjudicated by experts. Systolic BP was categorized into <120 mmHg (n=4385), 120-129 mmHg (n=4000), 130-139 (n=2066), and hypertension was categorized into controlled (<140/90 mmHg on treatment) (n=8378), and uncontrolled (>140/90 mmHg) (n=5364). Incident acute CHD was defined as definite or probable myocardial infarction (MI) or acute CHD death. CVD death was defined as acute CHD, stroke, heart failure or other cardiovascular disease related. Cox proportional hazards models estimated the hazard ratios (HR) for incident CHD by BP categories, adjusting for sociodemographics and CHD risk factors. Results: The 23,393 participants free of CHD at baseline were followed for a median of 4.4 years. Mean age was 64.1, 58% were women and 42% were black. There was a significant interaction between sex and BP categories, therefore analyses were stratified by sex. There were 252 non-fatal and fatal acute CHD events among women and 407 among men. Among women, compared with SBP<120 mmHg, BP categories above SBP 120 mmHg were associated with incident CHD (adjusted HR for SBP120-129 mmHg=1.94 {95% CI 1.04-3.62]; SBP 130-139 mmHg=1.92 {0.95-3.87}; controlled HTN=2.16 {1.25-3.75}; uncontrolled HTN=3.25 {1.87-5.65}) in fully adjusted models. Among men, only uncontrolled HTN was associated with incident CHD (HR=1.55 {1.11-2.17}). Conclusion: In this sample, preHTN may be associated with incident CHD among women but not men.