Sex Differences in Heart Transplantation Outcomes

Background: The U.S. heart transplant (HT) allocation policy was revised in 2018 with known sex differences in short-term outcomes; however, whether these translate to longer-term outcomes are unknown. Objectives: The authors sought to investigate long-term sex-specific waitlist and post-HT outcomes following this policy change. Methods: Waitlist cohort: Adults (≥18 years) listed for first-time, single-organ HT were identified using the United Network for Organ Sharing Registry between October 18, 2018, and October 17, 2023. Multivariable Fine-Gray competing risk analyses assessed: 1) rates of HT and 2) delisting due to death or clinical deterioration by sex. Transplant cohort: over the same time period, survival of first-time single-organ, HT recipients was analyzed by sex using multivariable Cox regression. Results: Among 15,422 waitlist candidates since 2018 (26.3% women), women had a higher rate of HT than men (adjusted subdistribution HR (aSHR): 1.24; 95% CI: 1.18-1.31; P < 0.001) and lower rate of delisting for death or clinical deterioration (aSHR: 0.81; 95% CI: 0.70-0.94; P = 0.005). Among 12,892 HT recipients (27.4% women), women had a higher adjusted post-HT mortality than men at 1-year and 5-years of follow-up (aHR: 1.14; 95% CI: 1.02-1.28; P = 0.019 and aHR:1.14; 95% CI: 1.02-1.27; P = 0.021, respectively). Conclusions: Five years after implementation of the 2018 allocation policy, women have higher rates of HT and lower delisting due to death or clinical deterioration as compared to men with lower long-term post-HT survival.