Race and Beta‐Blocker Survival Benefit in Patients With Heart Failure: An Investigation of Self‐Reported Race and Proportion of African Genetic Ancestry

Abstract

Background It remains unclear whether beta‐blockade is similarly effective in black patients with heart failure and reduced ejection fraction as in white patients, but self‐reported race is a complex social construct with both biological and environmental components. The objective of this study was to compare the reduction in mortality associated with beta‐blocker exposure in heart failure and reduced ejection fraction patients by both self‐reported race and by proportion African genetic ancestry. Methods and Results Insured patients with heart failure and reduced ejection fraction (n=1122) were included in a prospective registry at Henry Ford Health System. This included 575 self‐reported blacks (129 deaths, 22%) and 547 self‐reported whites (126 deaths, 23%) followed for a median 3.0 years. Beta‐blocker exposure ( BB exp) was calculated from pharmacy claims, and the proportion of African genetic ancestry was determined from genome‐wide array data. Time‐dependent Cox proportional hazards regression was used to separately test the association of BB exp with all‐cause mortality by self‐reported race or by proportion of African genetic ancestry. Both sets of models were evaluated unadjusted and then adjusted for baseline risk factors and beta‐blocker propensity score. BB exp effect estimates were protective and of similar magnitude both by self‐reported race and by African genetic ancestry (adjusted hazard ratio=0.56 in blacks and adjusted hazard ratio=0.48 in whites). The tests for interactions with BB exp for both self‐reported race and for African genetic ancestry were not statistically significant in any model ( P >0.1 for all). Conclusions Among black and white patients with heart failure and reduced ejection fraction, reduction in all‐cause mortality associated with BB exp was similar, regardless of self‐reported race or proportion African genetic ancestry.