Impact of pre-existing frailty on survival outcomes in solid-organ transplant candidates and recipients: A meta-analysis

Background: There is controversy surrounding the association between preexisting frailty and increased mortality in candidates and recipients of solid-organ transplants. This meta-analysis aimed to evaluate the impact of preexisting frailty on survival outcomes in solid-organ transplant candidates and recipients. Methods: A systematic search was conducted in the PubMed, Web of Sciences, and Embase databases until October 2, 2023. Two reviewers independently selected the eligible studies according to the PECOS criteria: Participants (candidates and recipients of solid-organ transplants), Exposure (frailty), Comparison (no-frailty), Outcomes (waitlist or posttransplant mortality), and Study design (retrospective or prospective cohort studies). The pooled effects were summarized by pooling the adjusted hazard ratio (HR) with 95 % confidence intervals (CI) for the frail patients than those without frailty. Results: Sixteen studies with 10091 patients met the eligibility criteria. Depending on the frailty tools used, the prevalence of frailty in solid-organ transplant candidates/recipients ranged from 4.6 % to 45.1 %. Frailty was significantly associated with an increased risk of waitlist mortality (HR 2.44; 95 % CI 1.84-3.24) and posttransplant mortality (HR 2.23; 95 % CI 1.61-3.09) in solid-organ transplant candidates and recipients, respectively. Subgroup analyses showed that the association of preexisting frailty with waitlist mortality and posttransplant mortality appeared to stronger in kidney transplant candidates (HR 2.70; 95 % CI 1.93-3.78) and lung transplantation recipients (HR 2.52; 95 % CI 1.23-5.15). Conclusion: Frailty is a significant predictor of reduced survival in solid-organ transplant candidates and recipients. Assessment of frailty has the potential to identify patients who are suitable for transplantation.