Repeat Transplantation with High-KDPI Kidneys: A Mate-Kidney Analysis

Background Initial and subsequent kidney transplantation improves survival compared to continued dialysis. We compared initial and repeat deceased-donor kidney transplantation outcomes at different kidney donor profile index (KDPI) levels using an adjusted mate-kidney model. Materials and Methods Deceased donors whose kidneys were transplanted into adults were identified from the organ procurement and transplant network/united network for organ sharing database. Patients received peri-operative induction and maintenance tacrolimus/mycophenolate. Transplant pairs were stratified by KDPI: 0-20% (best), 21-85% (average), and 86-100% (marginal). Delayed graft function (DGF), graft failure, death, and graft failure with death as competing outcomes were compared between re-transplantation and first-time recipients. Results Transplantations from 52,218 donors to 104,436 recipients between 2000 and 2022 were included. In adjusted models, the DGF odds increased by 38% in repeat recipients ( p <0.001). Hazard ratios (HR) for graft failure (HR:1.12, 95%confidence interval 1.07, 1.17), death (HR:1.14, 95%CI 1.09, 1.20), and graft failure with competing risk of death (HR:1.11, 95% CI 1.04, 1.18) were modest but significant ( p <0.001). DGF and graft failure risk with competing death significantly increased with increasing KDPI. Conclusion Our study suggests that the long-term re-transplantation risks are modest. “Marginal kidneys” have the potential for re-transplantation in selected patients. Selective use of these kidneys would benefit patients undergoing re-transplantation.