Abstract MP15: Mediation Effects of Social, Behavioral, and Metabolic Risk Factors on Racial Disparities in Cardiovascular Disease Mortality in US Adults

Abstract

Background: Traditional cardiovascular disease (CVD) risk factors contribute to racial disparities in CVD mortality. However, there are scarce data on the role of social determinants in these disparities. Methods: A nationally representative sample of 50,808 individuals aged ≥20 years from NHANES 1999-2018 were included in the analysis. Data on social, behavioral, and metabolic factors were collected in each NHANES survey. CVD deaths were ascertained from linkage to the National Death Index with follow-up through 2019. Multiple mediation analysis was used to simultaneously investigate the contribution of each risk factor to racial differences in CVD mortality. Results: Over an average 9.4 years of follow-up, 2,589 CVD deaths were confirmed. Age- and sex-adjusted CVD mortality rates (95% CI) per 100,000 were 380.1 (334.0, 437.3) in White, 479.6 (393.3, 592.5) in Black, 288.2 (214.1, 397.8) in Hispanic, and 251.2 (140.9, 502.8) in other racial/ethnic populations. After adjusting for all risk factors in the table, individuals who were unemployed, had a low family income, did not own a home, were not married or living with a partner, were a current smoker, reported no leisure time physical activity, slept <6 hours or >8 hours per day, had obesity, hypertension, diabetes, or hypercholesterolemia, or had an albumin-to-creatinine ratio ≥30 mg/g or estimated glomerular filtration rate <60 ml/min/1.73 m 2 were at significantly higher risk for CVD mortality. After adjusting for the above risk factors, the hazard ratio (95% CI) for the Black-White difference in CVD mortality decreased from 1.54 (1.34, 1.77) to 0.86 (0.75, 1.00). Family income, not being married or living with a partner, not owning a home, and unemployment explained 24.8%, 20.8%, 14.5%, and 12.8% of Black-White differences in CVD mortality, respectively. Conclusion: Social determinants of health play an important role in racial disparities in CVD mortality. These findings call for public health interventions beyond lifestyle changes and medical treatment.