Race/ethnicity is associated with ABO-nonidentical liver transplantation in the United States.

United Network for Organ Sharing (UNOS) policies allow for ABO-nonidentical liver transplantation (LT) in candidates with Model for End-Stage Liver Disease (MELD) scores greater than 30. Previous studies showed ABO-nonidentical LT resulted in an 18% and 55% net gain in livers for B and AB candidates. These results suggested that the current liver ABO allocation policies may need refinement. There are, however, strong associations between ABO blood groups and race/ethnicity. We hypothesized that race/ethnicity is associated with ABO-nonidentical LT and that this is primarily influenced by recipient ABO status. We examined non-status 1 adult candidates registered between July 1, 2013, and December 31, 2015. There were 27 835 candidates (70% non-Hispanic White, 15% Hispanic, 9% Black, 4% Asian, 1% Other/Multiracial). A total of 11 369 underwent deceased donor LT: 93% ABO identical, 6% ABO compatible, and 1% ABO incompatible. Black and Asian race/ethnicity were associated with increased likelihoods of ABO-nonidentical LT. Adjustment for disease etiology, listing MELD, transplant center volume, and UNOS region did not alter this association. Stepwise inclusion of recipient ABO status did eliminate this significant association of race/ethnicity with ABO-nonidentical LT. Blacks and Asians may be advantaged by ABO-nonidentical LT, and we suspect that changes to the existing policies may disproportionately impact these groups.