Assessment of U.S. heart transplantation equity as a function of race: Observational analyses of the OPTN database

Background: Racial disparities in heart transplantation (HT) outcomes are suspected but uncertain. The additional impact of a recent change in donor allocation on disparities in HT in the United States (US) is unknown. We hypothesize racial disparities in HT are present and may be worsened by new allocation practices. Methods: Cohort: Adults listed for HT before and after a heart allocation policy change (Era 1: Oct 18^th, 2015 - Oct 18^th, 2018, Era 2: Oct 18^th, 2018-June 30, 2021). The primary outcome was the rate of HT by race (Black vs. White), assessed using multivariable competing risk analysis (compete: waitlist removal for death or clinical deterioration). Final adjusted models included co-morbidities, SES and community-level Social Determinants of Health. The secondary outcome was waitlist removal for death or clinical deterioration. Results: Of 17,384 waitlist candidates (Era 1: 9,150, Era 2: 8,234), Black waitlist candidates had a lower rate of HT compared to White waitlist candidates in Era 1 (adjusted HR 0·90, 95 % CI 0·84-0·97, p = 0·0053) and in Era 2 (adjusted HR 0·81, 95 % CI 0·75-0·88, p <0·0001, era race interaction p=0·056). The rate of waitlist removal for death or deterioration was similar between races in Era 1 (adjusted HR 0·92, 95 % 0·77-1·1, p = 0·38), but increased for Black candidates in Era 2 (adjusted HR 1·34, 95 % CI 1·09-1·65, p = 0·0054, era race interaction p = 0·0051). Interpretation: Both the measured rate of transplantation and rate of delisting for death or clinical deterioration have worsened for Black compared to White waitlist candidates under the new allocation system. Causes for these disparities require further study. Funding: University of Minnesota Department of Cardiology funds.