Living unrelated donor kidney transplantation

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.