Donor Acute Kidney Injury, Delayed Graft Function, and Long-Term Graft Outcomes After Deceased-Donor Kidney Transplantation: A Propensity Score-Matched Competing-Risk Analysis

Background and Objectives: Donor acute kidney injury (AKI) is increasingly recognized in deceased-donor kidney transplantation, but its association with long-term graft outcomes remains controversial. We examined the association between donor AKI and death-censored graft failure (DCGF) while accounting for confounding and competing risks. Materials and Methods: We conducted a retrospective cohort study of 258 adult deceased-donor kidney transplant recipients (144 with AKI donors, 114 with non-AKI donors); all exposure, outcome, and follow-up data were verified against the primary registry before analysis. Propensity score matching (1:1, caliper 0.2 SD of the logit) created 100 matched pairs, with robust variance estimation clustered on pairs. DCGF was analyzed with Fine–Gray competing-risk regression, treating death with a functioning graft as a competing event: a primary donor-level model in the matched cohort and an exploratory post-transplant event model in the full cohort, with biopsy-proven acute rejection as a time-dependent covariate. Results: DGF occurred in 49.0% of recipients of kidneys from donors with AKI and in 33.0% of matched controls (p = 0.031), and lasted longer after donor AKI (median 10 vs. 7.5 days, p = 0.039); DGF frequency rose steeply with AKI Stages 2–3 (63.0% and 80.8%), whereas Stage 1 was comparable to the non-AKI group (23.4% vs. 33.0%). Donor AKI was not significantly associated with DCGF (sHR 1.91, 95% CI 0.95–3.86, p = 0.07; 5-year cumulative incidence 23.1% vs. 13.8%, Gray p = 0.064). In the exploratory post-transplant event model, DGF >14 days was associated with DCGF (sHR 3.29, 95% CI 1.53–7.07, p = 0.002), and time-dependent acute rejection was independently associated with DCGF (sHR 2.71, 95% CI 1.16–6.33, p = 0.021). Conclusions: Donor AKI was associated with a higher incidence and, in particular, a longer duration of DGF, but not significantly with long-term DCGF, and a clinically relevant association cannot be excluded. Prolonged DGF (>14 days) remained associated with DCGF after multivariable adjustment in the exploratory model. Kidneys from donors with AKI may be considered for transplantation within an appropriate clinical context, with particular attention to the early post-transplant course.