Abstract
BACKGROUND: The prevalence of obesity has dramatically increased. Candidates with obesity have higher waitlist mortality and are less likely to undergo liver transplantation (LT). The association of obesity with post-transplant mortality is inconsistent. METHODS: This study quantified the temporal trends in waitlist and transplant outcomes among patients with obesity using 2013-2023 SRTR data. Obesity class was defined as follows: no obesity (body mass index [BMI] of 18.5-29.0 kg/m(2)), class I obesity (BMI of 30.0-34.0 kg/m(2)), class II obesity (BMI of 35.0-39.0 kg/m(2)), and class III obesity (BMI of 40.0-55.0 kg/m(2)). The risks of waitlist and post-transplant mortality were quantified using adjusted competing risks and Cox proportional hazards. RESULTS: Among 103,640 candidates and 58,692 recipients, candidates with higher obesity classes had higher listing Model for End-Stage Liver Disease (MELD) scores that increased over time. Candidates with class III obesity were listed and transplanted at higher MELD scores than those without obesity, those with class I obesity, and those with II obesity. Nearly 40% of candidates with class III obesity had listing MELD scores of ≥30. From 2013-2017 to 2018-2023, the waitlist mortality decreased by 35% in candidates with class III obesity (subhazard ratio, 0.65 [95% CI, 0.58-0.73]; P <.001), and post-transplant mortality decreased by 20% for recipients with class III obesity (hazard ratio, 0.80 [95% CI, 0.66-0.96]; P =.02). However, over time, post-transplant mortality differed by obesity class, with no reduction in post-transplant mortality among recipients with class I or II obesity. CONCLUSION: LT candidates and recipients with class III obesity are being listed and transplanted at higher MELD scores with improvement in outcomes over time. Despite the higher risk, temporal trends in LT outcomes for this population are favorable. Given the higher disease severity at listing for candidates with class III obesity, referral patterns for LT evaluation in these patients should be evaluated.