Impact of Donor-Recipient Age Difference on Graft Function and Survival After Deceased Donor Kidney Transplantation

Background: Donor-recipient age difference (DRAD) is one of the reasons why patients on kidney waiting lists refuse to receive the offered organ. However, its impact on deceased donor kidney transplantation (DDKT) outcomes is still controversial. Methods: One hundred fifty-three kidney transplant recipients (KTRs) who received their first-time DDKT were enrolled. The KTRs were divided into groups by DRAD: group 1 (n = 74) (DRAD < 0) and group 2 (n = 79) (DRAD ≥ 0). The KTRs in group 2 were divided into 3 subgroups: DRAD 0 to 10 (n = 35), 10 to 20 (n = 32), and ≥ 20 (n = 12). The outcome measures included estimated glomerular filtration rate (eGFR), delayed graft function (DGF), acute rejection (AR), and graft and patient survival. Results: There were no significant differences in clinical outcomes between group 1 and 2 except eGFR until 5 years after DDKT. Among the subgroups of group 2, DGF, AR, patient survival, and eGFR until 5 years showed no significant differences. However, graft survival was significantly different (P = .015); in addition, in the DRAD ≥ 20 subgroup, graft survival decreased compared with that in the DRAD 10 to 20 subgroup and DRAD 0 to 10 subgroup (P = .020, P = .012, respectively). In a multivariate Cox proportional hazards analysis, the DRAD ≥ 20 subgroup showed a higher risk for graft failure than the DRAD 0 to 10 subgroup. Conclusions: Although donors were of the same age or older than recipients, DDKT showed acceptable graft outcomes. However, because donors over 20 years older than recipients showed a decreased graft survival, it might be important to consider this point in donor-recipient matching of DDKT.