Racial Differences in Fatal Out-of-Hospital Coronary Heart Disease and the Role of Income in the Atherosclerosis Risk in Communities Cohort Study (1987 to 2017)

Abstract

Black patients have higher incident fatal coronary heart disease (CHD) rates than do their White counterparts. Racial differences in out-of-hospital fatal CHD could explain the excess risk in fatal CHD among Black patients. We examined racial disparities in in- and out-of-hospital fatal CHD among participants with no history of CHD, and whether socioeconomic status might play a role in this association. We used data from the ARIC (Atherosclerosis Risk in Communities) study, including 4,095 Black and 10,884 White participants, followed between 1987 and 1989 until 2017. Race was self-reported. We examined racial differences in in- and out-of-hospital fatal CHD with hierarchical proportional hazard models. We then examined the role of income in these associations, using Cox marginal structural models for a mediation analysis. The incidence of out-of-hospital and in-hospital fatal CHD was 1.3 and 2.2 in Black participants, and 1.0 and 1.1 in White participants, respectively, per 1,000 person-years. The gender- and age-adjusted hazard ratios comparing out-of-hospital and in-hospital incident fatal CHD in Black with that in White participants were 1.65 (1.32 to 2.07) and 2.37 (1.96 to 2.86), respectively. The income-controlled direct effects of race in Black versus White participants decreased to 1.33 (1.01 to 1.74) for fatal out-of-hospital and to 2.03 (1.61 to 2.55) for fatal in-hospital CHD in Cox marginal structural models. In conclusion, higher rates of fatal in-hospital CHD in Black participants than in their White counterparts likely drive the overall racial differences in fatal CHD. Income largely explained racial differences in both fatal out-of-hospital CHD and fatal in-hospital CHD.