Kidney Transplant outcomes in patients with and without type 2 diabetes mellitus

INTRODUCTION: This study aimed to estimate the impact of type II diabetes (DM-II) on kidney transplant outcomes and graft utility. METHODS: A nationwide, registry-based study compares outcomes for all primary kidney transplantations performed between 2000 and 2022 in the Netherlands in DM-II patients (761 deceased and 364 living donor procedures) with nondiabetic controls. RESULTS: Short-term (≤90 days) transplant outcomes for living donor procedures were similar for DM-II and nondiabetic controls. Deceased donor transplantations in DM-II patients were associated with an increased incidence of delayed graft function (p < 0.0002), and a doubling of 90-day mortality (HR: 2.19 [95% CI: 1.49-3.23], p < 0.0001). Evaluation of long-term graft survival, with death as competing risk, indicated an equal (sub-distribution hazard rate [sHR] 0.95 [0.74-1.23]), respectively, compromised (sHR 1.91 [1.37-2.65]; p < 0.001) survival for grafts from deceased or living donors. DM-II profoundly impacted recipient survival (HR for death, respectively, 1.63 [1.45-1.82] and 1.81 [1.51-2.17]; p < 0.001) for recipients of a deceased or living donor graft (nondiabetic recipient is reference), with cardiovascular event and infection as dominant causes of death. The compromised recipient survival profoundly impacted the utility of kidney transplantations (p < 0.001). CONCLUSIONS: Despite excellent graft survival, the efficacy of kidney transplantations in DM-II patients is compromised by reduced recipient survival. Cause of death distribution suggests a role for immunosuppressive regimens in the excess mortality observed. A shift in focus from optimized transplant to optimized patient survival is warranted for DM-II patients. Moreover, the conflict between increasing incidences of DM-II, a lower transplant utility, but persistent donor organ shortages, calls for development of novel organ allocation strategies.