Beyond 75: Graft Allocation and Organ Utility Implications in Liver Transplantation

Abstract

Background. The global surge in aging has intensified debates on liver transplantation (LT) for candidates aged 75 y and older, given the prevalent donor scarcity. This study examined both the survival benefits and organ utility of LT for this age group. Methods. A total of 178 469 adult LT candidates from the United Network for Organ Sharing database (2003–2022) were analyzed, with 112 266 undergoing LT. Post-LT survival outcomes and waitlist dropout rates were monitored across varying age brackets. Multivariable Cox regression analysis determined prognostic indicators. The 5-y survival benefit was assessed by comparing LT recipients to waitlist candidates using hazard ratios. Organ utility was evaluated through a simulation model across various donor classifications. Results. Among candidates aged 75 y and older, 343 received LT. The 90-d graft and patient survival rates for these patients were comparable with those in other age categories; however, differences emerged at 1 and 3 y. Age of 75 y or older was identified as a significant negative prognostic indicator for 3-y graft survival (hazard ratio: 1.72 [1.20-2.42], P < 0.01). Dropout rates for the 75 y and older age category were 12.0%, 24.1%, and 35.1% at 90 d, 1 y, and 3 y, respectively. The survival benefit of LT for the 75 y and older cohort was clear when comparing outcomes between LT recipients and those on waitlists. However, organ utility considerations did not favor allocating livers to this age group, regardless of donor type. Comparing 3-y patient survival between LT using donors aged 60 y and younger and older than 60 y showed no significant difference (P = 0.50) in the 75 y or older cohort. Conclusions. Although LT offers survival benefits to individuals aged 75 y and older, the system may need rethinking to optimize the use of scarce donor livers, perhaps by matching older donors with older recipients.