Changes and mediators of survival disparity among Black liver transplant recipients in the United States.

A landmark 2002 study identified Black liver transplant (LT) recipients as having lower post-LT survival compared to other races. While persistent disparities exist, changes over time and mediating factors are understudied. Capturing LT recipients between 2002 and 2018 in UNOS, we used logistic regression and Cox proportional-hazard models to calculate differences in post-LT mortality among races. We examined interactions between transplant year and race. A mediation analysis assessed biologic and environmental factors potentially associated with race differences in post-LT survival. The cohort included 46,997 LT recipients (3898 Black;36,560 White;6539 Hispanic). In most years, Black (vs. White) LT recipients had a higher probability of age-adjusted mortality, not observed among Hispanics. In multivariable analysis, Blacks (vs. Whites) had higher (aHR = 1.15, 95% CI 1.07-1.24), whereas Hispanics had lower (aHR = 0.78, 95% CI 0.72-0.83) risk of mortality. Differences in post-LT mortality among Blacks (vs. Whites) narrowed between 2002 and 2009, were similar between 2010 and 2013, and may have worsened between 2014 and 2018. Race differences were larger for mortality beyond 1-year post-LT (vs. within 1-year), and among non-HCV (vs. HCV). Alcohol-associated liver disease (ALD) was the strongest mediator (13.9%, 95% CI 8.7-32.7%) of the Black-White disparity in 2010-2018. Our analyses suggest disparities may worsen with longer follow-up, as HCV recedes with elimination efforts, and with further increases in ALD.