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

Background. 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. Methods. 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. Results. 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. Conclusions. While BMI >= 45 is associated with modestly lower patient survival, careful selection may equalize these numbers.

Automated summary

This study evaluates the impact of BMI on liver transplant candidacy and post-transplant outcomes, indicating that patients with BMI >= 40 may have slightly lower survival rates post-LT, but careful selection could potentially equalize these numbers.