Abstract MP07: Racial Differences in Incident CHD in Observational Population-based Studies

Background: In the modern era, black men have twice the risk for fatal CHD versus white men, with similar incidence of total CHD. To examine secular trends in these findings, we compared the risk for incident fatal, nonfatal and total CHD by race across three US cohorts from different time periods. Methods: We analyzed data from blacks and whites in the Atherosclerosis Risk In Communities (ARIC) study (n=14,967, all 45-64 years of age, baseline 1987-1989), the Cardiovascular Health Study (CHS, n=4,626, all ≥65 years of age, baseline 1989-1993) and the REasons for Geographic and Racial Differences in Stroke (REGARDS) study (13,115 participants 45-64 years of age, 7,493 participants ≥65 years of age, baseline 2003-2007) who were free of CHD at baseline. Participants were followed for up to 10 years for fatal or nonfatal CHD. Analyses were stratified by age and gender and adjusted for similar risk factors across cohorts. Results: After age adjustment, black men 45-64 years of age in ARIC and REGARDS had higher risk for fatal CHD and similar risk for nonfatal and total CHD compared with their white counterparts (Table). After further adjustment for risk factors, blacks had similar risk for fatal CHD and lower risk for nonfatal and total CHD. A higher age-adjusted risk for fatal CHD and lower multivariable-adjusted risk for nonfatal CHD was also found among black versus white men ≥65 years of age in REGARDS; however, these associations were attenuated/absent in CHS. Among women 45-64 years of age in ARIC and REGARDS, blacks had higher age-adjusted risk for fatal, nonfatal and total CHD which were attenuated after adjustment for risk factors. There was no association between black race and CHD among women ≥65 years of age. Conclusion: Black-white disparities in the incidence of fatal CHD have remained similar for many years, particularly among those <65 years of age, and are explained by risk factors. The higher risk for fatal CHD is more striking among black men who consistently shown similar risk for total CHD compared with white men across cohorts.