Sex-Based Disparities in Heart Transplantation in Teenagers.

Background: Heart transplantation in teenagers has not been well studied. Teenage recipients have unique considerations that influence outcomes-complexity of cardiac disease, wide range of donor sizing and age, mechanical support options, and medication nonadherence. We sought to analyze the outcomes of heart transplantation in teenagers, focusing on sex-based disparities.

Methods: The United Network for Organ Sharing dataset was queried for patients 13 to 19 years of age who underwent heart transplantation from 2002 to 2021. Patients were divided into two groups based on sex. Baseline clinical characteristics were compared, along with an analysis of survival data. The primary outcome of interest was freedom from death or retransplantation.

Results: Heart transplantation was performed in 2320 teenagers; 812 (35.0%) were female. Female recipients were smaller (54.0 vs. 62.0 kg, p < 0.0001) and less likely to have congenital heart disease (26.5 vs. 31.6%, p < 0.0001). Female patients also had fewer pre-transplant ventricular assist devices (24.7 vs. 32.2%, p = 0.0002). By multivariable analysis, female sex was independently associated with lower survival (HR 1.26 [CI 1.08-1.48], p = 0.003). Sex-mismatched female recipients had significantly lower survival than sex-matched male recipients (HR 1.29 [CI 1.06-1.58], p = 0.009). Donor: recipient age difference < 5 years and donor: recipient weight > 1.2 were independent predictors of higher survival (p < 0.05).

Conclusions: Female teenagers have lower survival following heart transplantation than their male counterparts. Male donor-female recipient transplants have the lowest survival among sex-matching groups. The use of organs from oversized or younger donors in teenagers may be considered to help improve post-transplant survival.