Weighing the risks: Morbid obesity and diabetes are associated with increased risk of death on the liver transplant waiting list

Abstract

Obesity is a growing problem in liver transplant (LT) candidates, paralleling the US obesity epidemic and increase in LT for non-alcoholic steatohepatitis (NASH). While post-LT survival appears to be similar in obese and non-obese patients, data are scarce regarding risk of waitlist dropout in patients with morbid obesity (BMI≥40kg/m2 ). We examined the impact of obesity on waitlist mortality and evaluated predictors of dropout in LT candidates with morbid obesity or NASH. Competing risk analyses were performed in candidates listed between 3/2002-12/2013 to evaluate predictors of waitlist removal or death. Variables with P-value <.05 in univariable models or clinically relevant were included in multivariable models. Eighty-four thousand two hundred and fifty-four patients (34% female, median age 55, 15% Hispanic) were included. Compared to those with BMI 25-29.9kg/m2 , candidates with BMI≥40kg/m2 were more likely to be female (46% vs 28%), diabetic (25% vs 18%) and have NASH (35% vs 13%); all P<.001. After adjusting for well-recognized predictors of waitlist dropout, including ascites severity, morbid obesity (HR=1.27, CI 1.20-1.36) and diabetes (HR=1.14, CI 1.11-1.17) were independent predictors of dropout. Morbid obesity remained a predictor (HR=1.27, CI 1.10-1.47) of dropout in patients without ascites (24%). In NASH patients, morbid obesity (HR=1.21, CI 1.07-1.37) and diabetes (HR=1.15, CI 1.06-1.23) were also associated with a higher dropout risk. In patients with morbid obesity, diabetes trended towards a higher dropout risk but was not significant (HR=1.12, CI 0.995-1.26). Morbid obesity and diabetes are independent predictors of death in LT candidates.