Influence of body fat tissue on outcomes in patients undergoing hepatectomy or liver transplantation: a systematic review and meta-analysis

Objective:The purpose of this study is to investigate potential associations between body fat composition and postoperative outcomes in patients with hepatectomy or liver transplantation. Methods:Three online databases, including Embase, PubMed, and the Cochrane Library, were thoroughly searched for literature describing the relationship between body fat composition and outcomes of patients with liver surgery from the start of each database to 29 October 2023. The Newcastle-Ottawa Scale was used to rate the quality of the studies. Results:This analysis included a total of 29 articles with a combined patient cohort of 6435 individuals. The results demonstrated that patients with high intramuscular fat content (IMFC) had significantly inferior overall survival (OS) [hazard ratio (HR): 2.07, 95% CI: 1.69-2.53, P<0.001] and recurrence-free survival (RFS) (HR: 1.61, 95% CI: 1.20-2.16, P=0.002) and a higher risk of major complications (HR: 2.20, 95% CI: 1.59-3.05, P<0.001). We also found that the presence of high visceral-to-subcutaneous fat tissue ratio (VSR) in patients with liver surgery was significantly related to poorer OS (HR: 1.70, 95% CI: 1.44-2.00, P<0.001) and progression-free survival (PFS) (HR: 1.29, 95% CI: 1.11-1.50, P=0.001) and a higher major complication rate (HR: 2.31, 95% CI: 1.17-4.56, P=0.016). Besides, the synthesized findings indicated there is no significant correlation between visceral fat tissue and survival outcomes or postoperative complications. Conclusion:In summary, preoperative IMFC and VSR have the potential to forecast poorer OS and RFS and a higher risk of complications for patients undergoing hepatectomy or liver transplantation.