Abstract P150: Association of Cholesterol Measures With Coronary Heart Disease Risk in Blacks and Whites in the Reasons for Geographic and Racial Differences in Stroke Study (regards)

Introduction: Abnormal plasma lipid levels associate with coronary heart disease (CHD) risk. Race interaction for these associations are not established. Hypothesis: We hypothesized that the association of HDL, LDL, and triglyceride with CHD is stronger in whites versus blacks. Methods: The REasons for Geographic and Racial Differences in Stroke (REGARDS) cohort recruited 30,283 black and white individuals aged 45+ from the contiguous U.S. from 2003-7. Participants were followed until December 31, 2016 for CHD events (i.e., myocardial infarction or CHD death), participants with history of CHD at baseline were excluded. Cox regression models were used to assess the association between baseline lipids and incident CHD events adjusting for traditional cardiovascular risk factors. Results: With 23,894 participants (57.8% white and 58.4% female, mean age 64.11± 9.32), over a median 9.9 years of follow-up, 1,487 CHD events occurred (615 among blacks). Overall, higher total Cholesterol, LDL cholesterol, and triglycerides were associated with increased risk of CHD in both blacks and whites with no evidence of a race interaction (Table 1). For HDL, the point estimate was more protective in whites (HR 0.90) than in blacks (HR 0.98), but the interaction was non-significant (p=0.15). However, when HDL was stratified into clinical categories (<40, 40-59, and ≥60), the reduction in point estimates was maintained among whites (HR 1.00, 0.88, and 0.74) but not among blacks (HR 1.00, 1.31, and 1.19) for HDL <40, 40-59, and ≥60 respectively, p-interaction 0.01. Conclusion: Total cholesterol, LDL, and triglycerides predict CHD risk equally in blacks and whites in the REGARDS study, however there is heterogeneity in the protective effect by race, especially when traditional clinical categories are used. In whites, higher HDL is associated with reduced risk, whereas in blacks the association is not maintained. These findings suggest that HDL levels are a more viable metric for white than blacks to predict CHD risk.