Association between HOMA2 based beta-cell function or insulin resistance and long-term outcomes in kidney transplant recipients with type 2 diabetes

Type 2 diabetes (T2D) is a common comorbidity in kidney transplant recipients, representing a significant proportion of the candidate pool. Post-kidney transplantation management of T2D remains challenging, leading to inferior long-term outcomes compared to non-diabetic recipients. This study aimed to assess the association between Homeostatic Model Assessment 2 (HOMA2) derived insulin resistance and beta-cell function on kidney graft outcomes in T2D kidney transplant recipients. We conducted a monocentric retrospective study at the University Hospital of Lille, including all consecutive adult T2D patients who underwent kidney transplantation between January 2007 and December 2018. HOMA2 indexes (HOMA2 IR for insulin resistance and HOMA2 B for beta-cell function) were calculated at one-year post-transplantation. Primary endpoint was graft survival and secondary endpoints were death-censored graft survival, patient survival and post-transplant metabolic control. Among 1620 kidney transplant recipients, 138 patients with T2D were included, with a median follow-up of 1837 days [1283-2726]. HOMA2 IR was significantly associated with an increased risk of kidney graft failure or death (HR per unit = 1.11 (1.02-1.21). Beta-cell function was not associated with graft prognosis, but decreased beta-cell function was associated with poorer metabolic control over time. This study highlights the significance of insulin resistance as a potential determinant of long-term outcomes in T2D kidney transplant recipients.