Effect of Donor-Recipient Age Difference on Liver Transplant Outcomes

The global organ shortage and aging population lead to the use of liver grafts with increasing donor-recipient age discrepancies. This study evaluated the impact of donor-recipient age mismatch on posttransplant outcomes.

Organ Procurement and Transplantation Network/United Network for Organ Sharing data were analyzed, stratifying donor-to-recipient pairs by age difference: young-to-old (≥20 y), old-to-young (≥20 y), and similar-age group (<20 y difference). Liver life expectancy was calculated by adding recipient survival time to donor age. Graft survival was assessed using Kaplan-Meier and Cox regression analyses.

Among 111 125 liver transplantation recipients performed between 2005 and 2024, young-to-old group (≥20 y younger) had the highest 5-y graft survival (77.8%), followed by similar-age group (76.0%). Old-to-young group (≥20 ys older) had the lowest survival (69.9%) (P < 0.001). Patient survival did not differ significantly (P = 0.849). A subanalysis including all liver transplants available since database inception identified 4230 livers (2.6%) reaching ≥80 y, 687 (0.4%) reaching ≥90 y, and 34 (0.02%) reaching ≥100 y. Among 188 recipients ≤35 y old who received livers from donors ≥70 y old, graft survival was inferior (P < 0.001), and patient survival remained similar (P = 0.271). In recipients ≤40 y old, graft survival declined incrementally with each additional donor age decade. In this subgroup, when restricted to Model for End-Stage Liver Disease ≥35, grafts from donors >60 or >70 y old showed markedly reduced 1-y survival of 81%-82%. The multivariate analysis confirmed an independent 10% increase in 1-y graft failure in the old-to-young compared with similar-age group (P = 0.021).

A greater donor-to-recipient age difference, particularly with older donors, negatively impacted liver graft survival. However, patient survival was not affected, supporting the use of older grafts to optimize transplant benefits for selected recipient populations.