Impact of Delayed Graft Function on Kidney Transplant Outcomes

Background: Delayed graft function (DGF) is a frequent complication following deceased donor kidney transplant. The revised allocation policy mandates a wider geographical distribution of kidneys from deceased donors resulting in prolonged cold time and higher rates of DGF. Our study explores the impact of duration of DGF on graft function and survival. Methods: We reviewed records of 687 patients who received deceased donor kidney transplant (DDKT) from 2020 to 2023 at the University of Michigan Transplant Center. Patients were grouped based on occurrence of DGF (need for dialysis within 7 days of transplant) and duration (0-14, 15-30, and >30 days). We compared donor, and recipient characteristics across 4 groups. Graft outcomes across 4 groups were compared via serum creatinine at last follow-up and also via Kaplan-Meier Survival Curves. Cox proportional hazard models were constructed to account for donor and recipient factors for graft loss. Results: Of the 687 DDKT, 466 (68%) had no DGF and 221 (32%) developed DGF. Of 221 patients with DGF, 135 (61%) required dialysis for <14 days, 58 (26%) for 15-30 days, and 28 (13%) for more than 30 days. Donor risk factors that were associated with severe DGF include donation after cardiac death, death by anoxia, history of hypertension, and diabetes mellitus (p<0.05). Recipient risk factors for severe DGF include usage of anticoagulation, and Midodrine, African American race, and history of diabetes (p<0.05). Serum creatinine varied across 4 groups and was lowest among patients with no DGF and highest among patients with most severe DGF (1.1±0.6, 1.7±0.6, 2.3±0.9 and 2.4±1.4 mg/dL; p<0.001). Graft survival varied across 4 groups and was lowest among recipients requiring dialysis for more than 30 days (see Figure 1, p<0.001). On multi-variate analyses, severity of DGF, donor age and donor history of diabetes were associated with graft loss. Conclusion: Duration of DGF has a negative impact on graft function and survival. New strategies are needed to improve organ preservation and manage patients after transplant to reduce the duration of DGF and subsequently graft loss.