Abstract MP77: Projected Impact of Shifting Population Distributions of Blood Pressure on Rates of Coronary Heart Disease, Heart Failure and Stroke: The Atherosclerosis Risk in Communities Study

Abstract

Introduction: Rates of cerebrovascular disease, heart failure (HF), and coronary heart disease (CHD), increase progressively as blood pressure rises. Several authors have estimated the theoretical effects of shifting the population distribution of blood pressure; however few studies have examined the degree to which modest decrements in blood pressure affect HF incidence, or included a racially diverse population. Methods: Incident HF was identified by a first hospitalization with discharge diagnosis code of 428.X. Incident hospitalized (definite or probable) CHD and stroke were classified according to protocol. We used multivariable regression to estimate incidence rate differences (IRD) for HF, CHD, and stroke that could be associated with a two mm Hg reduction in systolic blood pressure (SBP) in 15,744 participants from the Atherosclerosis Risk in Communities Study. Results: Over a mean of 18.3 years of follow up, age-adjusted incidence rates for HF, CHD, and stroke were higher among African American than Caucasians (Table 1). After adjusting for antihypertensive use, gender, and age, a two mm Hg decrement in SBP across the total population was associated with an estimated 24/100,000 person-years (PY) and 39/100,000 PY fewer incident HF events in Caucasians and African Americans, respectively. The projected disease reductions were of smaller absolute magnitude for incident CHD and incident stroke. Extrapolation to the African American and Caucasian U.S. populations age greater than 45 years suggests that a two mmHg decrement in SBP could result in approximately 22,000 fewer incident HF events, 15,000 fewer incident CHD events, and 5,000 fewer incident stroke events annually. Conclusion: Our results suggest that modest shifts in SBP, consistent with what could theoretically be achieved through population level lifestyle interventions, could substantially decrease the incidence of HF, stroke, and CHD in the United States, especially among African American populations.