Early post–lung transplant weight gain is associated with increased long-term recipient survival
Objective Organ transplantation is associated with significant physiologic, metabolic, and medication-related changes that impact recipient weight. This study investigates the association of post-transplant body mass index trajectory with survival in lung transplant recipients. Methods This is a retrospective study of all adult lung transplants performed in the United States between 2005 and 2013. Recipients were stratified by body mass index change at 1 year post-transplant relative to pretransplant into quartiles: decreased: <–1.16, stable: -1.16-0.98, and increased: >0.98 kg/m2. All-cause mortality was analyzed with Kaplan–Meier and Cox proportional hazards models adjusted for relevant donor and recipient variables. Subgroup analysis was performed in patients with body mass index with and without pretransplant obesity (body mass index ≥30 kg/m2). Results Among 9709 lung recipients, median body mass index at 1 year post-transplant was 25.5 kg/m2, and median 1-year body mass index change was +0.98 kg/m2. Survival was highest in the increased body mass index group, followed by stable then decreased groups ( P < .001). On multivariable analysis, decreased body mass index was associated with increased risk of all-cause mortality (adjusted hazard ratio, 1.19, 95% CI, 1.11-1.27), whereas increased body mass index was associated with decreased risk of all-cause mortality (adjusted hazard ratio, 0.84, 95% CI, 0.79-0.89) compared with the stable group. Among those with pretransplant obesity, both increased and decreased groups had similar adjusted risk of mortality as the stable group. Conclusions Weight gain in the first year after lung transplantation is associated with a survival benefit, except in patients with pretransplant obesity, whereas weight loss is associated with long-term recipient mortality. Close attention should be directed toward weight trajectory in the postoperative period.
