Born to Be Accepted: Donor age Association With One-year Rejection in Deceased Donor Kidney Transplants

Kidneys from pediatric donors are underutilized, in part because of concern about acute rejection. This study evaluated the association between donor age and 1-y acute rejection after deceased-donor kidney transplantation.

We retrospectively analyzed Scientific Registry Of Transplant Recipients data from 2014 to 2025 for first-time, deceased-donor, adult kidney recipients. The primary outcome was any reported acute rejection episode within 12-mo posttransplant, modeled by multivariable generalized estimating equations logistic regression clustered by transplant center and restricted to pretransplant covariates. Donor age was a 5-level categorical variable with post hoc, data-derived cut-points at 3.5, 18.3, 34.3, and 61.3 y from locally estimated scatterplot smoothing inflection points. A secondary model split the reference group by en bloc versus non-en bloc procedures.

Among 136 182 recipients, 8803 had rejection events (6.5%). Donors <3.5 y (n = 2061) had an unadjusted rejection rate of 4.8% versus 6.5% for donors ≥3.5 y (P = 0.002). Adjusted odds were higher in every older stratum: 3.5-18.3 y (adjusted odds ratio 1.59; 95% CI 1.25-2.04), 18.3-34.3 y (1.61; 1.24-2.10), 34.3-61.3 y (1.97; 1.51-2.56), and >61.3 y (2.49; 1.88-3.28); all P < 0.001. Population-standardized adjusted probabilities increased from 3.9% (2.9-5.0) to 9.1% (8.2-10.0). En bloc allografts differed significantly from all four older strata; non-en bloc allografts from the 2 oldest only.

Younger ages of deceased-donors are associated with up to 60% lower adjusted odds of 1-y rejection. Donor age appears to have an independent association with early acute rejection.