Background: Living unrelated donors remain an underutilized resource, despite their high graft survival rates. In this article, we updated the long-term results of more than 2500 living unrelated donor transplants performed in the United States.
Methods: Between 1987 and 1998, 1765 spouse, 986 living unrelated, 27,535 living related, and 86,953 cadaver donor grafts were reported to the United Network for Organ Sharing Kidney Registry. Kaplan-Meier curves compared graft survival rates in stratified analyses, and a log-linear analysis adjusted donor-specific outcomes for the effects of 24 other transplant factors.
Results: The long-term survival rates for both spouse and living unrelated transplants were essentially the same (5-year graft survivals of 75 and 72% and half-lives of 14 and 13 years, respectively). The results were similar to that for parent donor grafts (5-year graft survival = 74% and half-life = 12 years) and were significantly (P = 0.003) better than cadaver donor grafts (5-year graft survival = 62% and half-life = 9 years). After adjusting for the presence of transplant factors known to influence survival rates, recipients of living unrelated donor kidney transplants still had superior outcomes compared with cadaver transplants.
Conclusions: Living unrelated kidney donors represent the fastest growing donor source in the United States and provide excellent long-term results. Encouraging spouses to donate could remove nearly 15% of the patients from the UNOS waiting list, effectively increasing the number of available cadaveric organs.