Evaluating the outcomes of donor-recipient age differences in young adults undergoing liver transplantation

Abstract

The current liver allocation system may be disadvantaging younger adult recipients as it does not incorporate the donor-recipient age difference. Given the longer life expectancy of younger recipients, the influences of older donor grafts on their long-term prognosis should be elucidated. This study sought to reveal the long-term prognostic influence of the donor-recipient age difference in young adult recipients. Adult patients who received initial liver transplants from deceased donors between 2002 and 2021 were identified from the UNOS database. Young recipients (patients 45 years old or below) were categorized into 4 groups: donor age younger than the recipient, 0-9 years older, 10-19 years older, or 20 years older or above. Older recipients were defined as patients 65 years old or above.To examine the influence of the age difference in long-term survivors, conditional graft survival analysis was conducted on both younger and older recipients.Among 91,952 transplant recipients, 15,170 patients were 45 years old or below (16.5%); these were categorized into 6,114 (40.3%), 3,315 (21.9%), 2,970 (19.6%), and 2,771 (18.3%) for groups 1-4, respectively. Group 1 demonstrated the highest probability of survival, followed by groups 2, 3, and 4 for the actual graft survival and conditional graft survival analyses. In younger recipients who survived at least 5 years post-transplant, inferior long-term survival was observed when there was an age difference of 10 years or above (86.9% vs. 80.6%, logrank p < 0.01), whereas there was no difference in older recipients (72.6% vs. 74.2%, log-rank p = 0.89). In younger patients who are not in emergent need of a transplant, preferential allocation of younger aged donor offers would optimize organ utility by increasing postoperative graft survival time.

Maximizing outcomes by donor-recipient age matching in liver transplantation

“…Data on the impact of donor-recipient age mismatch in liver transplantation have been mixed, with some data suggesting inferior outcomes when older grafts were used in younger recipients. [1] However, prior studies had methodological limitations. Most studies focused on recipients between the ages of 50 and 60 years [4] rather than younger recipients, with outcomes restricted to short-term outcomes.…”

“…Importantly, the authors found that the donor-recipient age difference was superior in prognostication long-term outcomes compared with the composite DRI or donor age alone. Based on their findings, the authors suggested that the liver allocation system should shift “toward an age-matched process so as not to disadvantage younger recipients and to optimize organ use.” 1 …”

“…Based on their findings, the authors suggested that the liver allocation system should shift "toward an age-matched process so as not to disadvantage younger recipients and to optimize organ use." [1] This study is commendable for several reasons. It is the first paper to assess long-term prognostic outcomes in younger patients (< 45 y old).…”

“…To meet the ever-increasing need for lifesaving liver transplants, transplant centers must consider an expanded donor pool, which includes use of livers from older donors. [1,2] However, because the liver allocation system in the United States is solely urgency based using the Model for End-Stage Liver Disease score, considerations of optimizing posttransplant outcomes and donor-recipient matching are left to the individual transplant center. In contrast to kidney transplantation, where the "best" organs are first allocated to patients with the longest-predicted survival, [3] no such policy exists in liver transplantation.…”

“…Data on the impact of donor-recipient age mismatch in liver transplantation have been mixed, with some data suggesting inferior outcomes when older grafts were used in younger recipients 1 . However, prior studies had methodological limitations.…”