Association of body mass index with post-liver transplant outcomes

Background: Patients with obesity have inferior outcomes after general surgery procedures, but studies evaluating post-liver transplant (LT) outcomes have been limited by small sample sizes or lack of granularity of outcomes. We evaluated the relationship between obesity and post-LT outcomes, including those observed in other populations to be obesity-related. Methods: Included were 1357 LT recipients prospectively enrolled in the ambulatory pre-LT setting at 8 U.S. centers. Recipient were categorized by body mass index (BMI, kg/m²): non-obese (BMI < 30), class 1 obesity (BMI 30–<35), and classes 2–3 obesity (BMI ≥ 35). Post-transplant complications were compared by BMI using Chi-square and rank-sum testing, logistic regression, Kaplan-Meier curves, and Cox regression. Results: Classes 2–3 obesity was associated with higher adjusted odds than non-obesity of venous thrombosis [adjusted odds ratio (aOR) 2.06, 95% CI 1.01–4.23, p =.047] and wound dehiscence (aOR 2.45, 95% CI 1.19–5.06, p =.02). Compared with non-obese recipients, post-LT hospital stay was significantly longer for recipients with classes 2–3 obesity [p =.01; median (Q1–Q3) 9 (6–14) vs. 8 (6–12) days) or class 1 obesity [p =.002; 9 (6–14) vs. 8 (6–11) days]. Likelihood of ICU readmission, infection, discharge to a non-home facility, rejection, 30-day readmission, and 1-year readmission were similar across BMI categories (all p >.05). Conclusion: Compared to non-obese recipients, obese recipients had similar post-LT survival but longer hospital stay and higher likelihood of wound dehiscence and venous thrombosis. These findings underscore that obesity alone should not preclude LT, but recipients with obesity should be monitored for obesity-related complications such as wound dehiscence and venous thrombosis.