Impact of body mass index on graft failure and overall survival following liver transplant

Goals: To assess the influence of body mass index (BMI) in the outcome of liver transplantation. Background: Body mass index appears to affect liver transplantation, independently of several risk factors. Study: A review of the United Network for Organ Sharing database included 32 515 liver transplants from 1992 through 2000 with at least one follow-up visit, of which 26 920 had information for determining BMI. The overall impact of elevated BMI (>25), and the impact of increasingly elevated BMI (25-40+) on graft failure rates and overall survival rates are assessed using proportional hazards regression. Results: Controlling for follow-up time, age, gender, race, number of comorbidities, and status 1 designation, the impact of BMI on survival was mixed. The risk of death was elevated for patients with low BMI (<19) and BMI values of greater than or equal to40. Compared with patients with BMI of 19-22, those with BMI > 25 had a decreased likelihood of death. This decrease was seen among patients with BMI of 25-34. Conclusion: BMI did not significantly affect rates of graft failure. Compared with patients with a BMI in the 'normal' range, those with moderately elevated BMI had decreased likelihood of death while patients with low BMI or extremely high BMI had increased likelihood of death.