Impact of waitlist weight change on outcomes in heart transplant recipients: a UNOS database analysis

While the effect of pre-transplant weight on patient outcomes following heart transplantation (HTx) has previously been studied, data regarding the impact of dynamic weight change prior to HTx are extremely limited. We sought to elucidate the interaction between HTx listing weight and weight change while waitlisted, and explore how that interaction impacts post-HTx survival in a continuous manner. Adult patients listed for HTx from 1987 to 2020 were identified from UNOS database. Three-dimensional restricted cubic spline analysis explored post-HTx survival relative to both changes in BMI/weight and BMI at time of HTx listing. Continuous predictor variables were analyzed with Cox proportional hazards method. 9,628 included patients underwent HTx. Median recipient age was 55 [IQR 46-62] years, and 21% were females. 53% of patients lost while 47% gained weight on the waitlist. Median BMI (27.6 kg/m [24.3-31.3] vs. 27.4 kg/m [24.2-30.9], paired p