Abstract P362: Racial Disparities in Cardiovascular Disease Mortality: Mediation by Socioeconomic Factors and Statin Use (The ELSA-Brasil Study)

Abstract

Background: Statins are an effective strategy to reduce CVD risk, however, treatment goals are not achieved especially among Blacks and “Pardos” in Brazil. Hypothesis: Socioeconomic differences and lack of statin treatment for primary CVD prevention can explain part of the elevated mortality risk of Blacks and “Pardos”. Methods: Data from the ELSA-Brasil cohort (15,105 civil servants, from 6 state capital cities), excluding Asians, Indigenous, those with prevalent CVD and missing information about race or statin use. Race was self-reported as Black, “Pardo” or White. Brazilian guidelines at baseline (2008) were used to define those eligible for statin treatment. Cox survival analysis determined the risk of CVD mortality for Black and “Pardo” compared to White (adjusted by age, sex, hypertension, diabetes, LDL-c, BMI and smoking). We used inverse odds ratio weighting technique to calculate mediation for socioeconomic factors (SEF) (education, income, and having health insurance) and statin use when indicated to determine the natural direct and indirect effects of race on CVD mortality. We estimated the percent mediation as the percent change between β coefficients with and without weights applied. Results: Among the 13,396 individuals, the mean age was 52±9 years, 55.2% were women, 54.2% were White, and 10.2% were taking statins. Adjusted Black and “Pardo”/White CVD mortality HR was 1.91 (CI 95% = 1.30-2.81, p<0,001). The direct effect of race on CVD mortality when considering the weight of SEF was 1.37 (CI 95% = 0.86-2.19) and considering the weight of statin use was 2.01 (CI 95% =1.36-2.98). SEF explained 51.5% (CI 95% = 17.0-60.2) and not using statins when indicated explained 7.8% (CI 95% = 4.2-23.3) of the racial inequality observed in CVD mortality risk (Table 1). Conclusions: The higher Black and “Pardo”/White CVD mortality risk is primarily explained by racial differences in SEF. Not using statins when there is indication for treatment increases in about 8% the CVD mortality risk for Blacks and “Pardos” compared to Whites.