Impact of Morbid Obesity on Liver Transplant Candidacy and Outcomes: National and Regional Trends.

Abstract

Body mass index (BMI) limits for liver transplant (LT) candidacy are controversial. In this study, we evaluate waitlist and post-LT outcomes, and prognostic factors and examine regional patterns of LT waitlist registration in patients with BMI ≥40 versus BMI 18-39. United Network for Organ Sharing (UNOS) data were analyzed to assess waitlist dropout, post-LT survival, and prognostic factors for patient survival. The distribution of waitlisted patients with BMI ≥40 was compared with the Centers for Disease Control Behavioral Risk Factors Surveillance System data to explore the rates of morbid obesity in the general population of each UNOS region. Post-LT outcomes demonstrate a small but significantly lower 1- and 3-y overall survival for patients with BMI ≥45. Risk factors for post-LT mortality for patients with BMI ≥40 included age >60 y, prior surgery, and diabetes on multivariable analysis. Model for End-Stage Liver Disease >30 was significant on univariable analysis only, likely due to the limited number of patients with BMI ≥40; however, median Model for End-Stage Liver Disease scores in this BMI group were higher than those in patients with lower BMI across all UNOS regions. Patients with BMI ≥40 had a higher waitlist dropout in 4 regions. Comparison with BRFSS data illustrated that the proportion of waitlisted patients with BMI ≥40 was significantly lower than the observed rates of morbid obesity in the general population in 3 regions. While BMI ≥45 is associated with modestly lower patient survival, careful selection may equalize these numbers.