Body weight parameters are related to morbidity and mortality after liver transplantation - A systematic review and meta-analysis

Weight gain and obesity are well-known clinical issues in liver transplantation (LTx). However, their impacts on patient outcomes remain unclear, as only the impact of pre-LTx BMI on survival has been meta-analyzed. We summarized and synthesized the evidence on pre- and post-LTx body weight parameters' relationships with post-LTx outcomes such as survival, metabolic and cardiovascular comorbidities, and healthcare utilization.; We followed the Cochrane Handbook for Systematic Reviews of Interventions' recommendations. Quality was assessed via a 19-item instrument. Odds ratios and 95% confidence intervals were calculated for outcomes investigated in ≥5 studies.; Our meta-analysis included 37 studies. Patients with pre-LTx BMI ≥30 kg/m and BMI ≥35 kg/m had lower overall survival rates than those with pre-LTx normal weight (72.6% and 69.8% vs. 84.2% p=0.02 and p=0.03, respectively). Those with pre-LTx BMI ≥30 kg/m had worse overall graft survival than normal weight patients (75.8% and 85.4%, p=0.003). Pre-LTx BMI and pre-LTx overweight were associated with new-onset diabetes (p<0.001 and p=0.015, respectively), but post-LTx BMI showed no relationship. No associations were evident with healthcare utilization.; Patients with BMI values ≥30 kg/m had worse patient and graft survival than those with normal weight. Few of the reviewed studies examined post-LTx body weight parameters or other relevant outcomes such as cardiovascular comorbidities. High heterogeneity as well as diverse definitions and operationalizations of measurement and outcomes severely impeded comparability.