Frailty as a predictor of poor outcomes among patients awaiting liver transplant: a systematic review and meta-analysis.

Aim: This review sought to evaluate the significance of a functional assessment for liver transplant candidates, i.e., frailty, in the pre-transplant setting and its association with mortality and morbidities.

Background: Liver transplantation (LT) remains the treatment of choice for patients with end-stage liver disease. Due to the shortage of organs for LT, a careful selection of suitable recipients is essential. Frailty, a measure of physiologic reserve and increased vulnerability to stressors, was initially used in geriatrics and then introduced to the field of transplantation for better patient selection.

Methods: PubMed, Scopus, and Web of Science databases were reviewed up until January 2023. The search terms included: "frail*", "liver", and "transplant*". A Meta-analysis was conducted for the hazard ratios (HRs) obtained from the COX regression models. Fifty-five studies were included in this review; ten were included in the meta-analysis.

Results: The prevalence of frailty varied from 2.82% to 70.09% in the studies. Meta-analysis showed that overall frailty had a significant association with mortality (pooled adjusted HR [95%CI]: 2.66 [1.96-3.63]). Subgroup analyses revealed that both the Liver Frailty Index and Fried Frailty Index were significantly associated with mortality. Furthermore, these studies have demonstrated that this population's frailty is associated with ascites, hepatic encephalopathy, and esophageal varices.

Conclusion: According to emerging evidence, frailty is associated with increased morbidity and mortality of the patients on the LT waiting list. Further randomized trials are required to determine the efficacy and safety of variable interventions in the frail population.