Increased Morbidity in Overweight and Obese Liver Transplant Recipients - A Single Centre Experience with 1325 Patients

Abstract

Introduction: Various studies from US and elsewhere have reported either similar outcome between obese and non-obese liver transplant recipients, or increased morbidity and overall poor patient and graft survival in obese patients. We aim to study the impact of BMI following adult liver transplantation. Methods: Data was retrieved from a prospectively maintained institutional database from 1994-2009. Patients were stratified into 4 BMI categories established by the WHO: underweight (< 18.5 kg/m2), normal weight (18.5 to < 25.0 kg/m2), over weight (>25.0 to < 30.0 kg/m2) and obese (>30.0 kg/m2). Primary outcome was to evaluate post-operative morbidity and secondary measures were overall patient and graft survival. Categorical variables were analysed by Χ2, and continuous variables by one-way ANOVA (p value < 0.05 was considered statistically significant). Kaplan Meier curves with log-rank comparison were used to study the effect of BMI categories on patient and graft survival. Results: 1400 adult transplants were identified. 1325 patients with available date were included, of which there were 47 underweight (3.5%), 643 normal weight (48.5%), 417 overweight (31.5%) and 218 obese (16.5%) patients. Post-operative chest infections were much more common in obese (14.2% vs 9.0%, p=0.038) and overweight recipients (17.7% vs 9.0%, p < 0.001) in comparison to normal weight recipients. Obese patients had significantly longer intensive care stay than normal weight patients (mean 4.1 vs 3.2 days, p=0.043). The length of post-operative hospital stay was significantly longer in obese (mean 21.5 days, p=0.009) and overweight patients (mean 22.4 days, p=0.000) in comparison to normal weight patients (mean 18.0 days). Similarly, ascitic or drain fluid sepsis was common in overweight patients in comparison to normal weight recipients (16.5 % vs 2.2%, p< 0.001). Overall, post-operative septic events were common in overweight (60.6%, p=0.001) and obese patients (61.0%, p=0.007) in comparison to normal weight patients (50.4%). There was no difference in overall graft survival (p=0.222) and patient survival (p=0.196) between the four groups by log-rank (Mantel-Cox). Conclusions: This is the largest and the only reported UK series on BMI and outcome following liver transplantation. Liver transplantation does lead to increased morbidity in terms of septic complications in overweight and obese patients, with consequent increased length of intensive care and hospital stay. Identifying these patients early and reducing BMI appropriately should be an important consideration to improve outcomes and for appropriate use of scarce resources.