UNOS Registry Analysis: How Does Heart Transplant Recipient Weight Affect Waitlist Days?

Body weight of heart transplant (HTx) recipients affects waitlist days. However, no prior report exists to articulate this in detail. The aim of this study is to analyze the effect of recipients' weight to HTx. The United Network of Organ Sharing (UNOS) registry was analyzed under the current allocation from 2018 to 2023. The cohort was divided into three even weight groups: low (<77.1 kg), middle (77.1-92.1 kg), and high (>92.1 kg). Candidate/donor demographics, weight distributions, waitlist days in UNOS Status, cumulative incidence of HTx and delisting, post-HTx survival, and cutoff weight for earlier HTx were analyzed. A total of 16,664 HTx recipients were included (5,535: low, 5,537: middle, and 5,592: high). Donors and recipients had a weight distribution mismatch (p = 0.003). For waitlist days, status 1 was comparable; however, the high group with status ≥2 had approximately twice longer waitlist days than the low group. The high group had a lower incidence of HTx (p < 0.001) and higher delisting (p = 0.02) than the low group. One year survival was comparable (p = 0.28). The weight cutoff for earlier HTx was 80 kg with a 21.6% increased rate of HTx (hazard ratio [HR] = 1.216; 95% confidence interval [CI], 1.171-1.263, p < 0.001). Recipients weighing <80 kg had earlier HTx and a higher incidence of HTx. The effect of pre-HTx weight management requires further study.