Supplementary Material for: Kidney Transplant outcomes in patients with and without type 2 diabetes mellitus.

Introduction: This study aims to estimate the impact of type-II diabetes (DM-II) on kidney transplant outcomes and graft utility.
Methods: A nation-wide, registry-based study that 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 non-diabetic controls.
Results: Short-term (≤90 days) transplant outcomes for living donor procedures were similar for DM-II and non-diabetic controls. Deceased donor transplantions in DM-II patients were associated with an increased incidence of delayed graft function (p<0.0002), and a doubling of 90-days 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 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 respectively (non-diabetic recipients reference):, with cardiovascular 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.