Use of Tacrolimus and the Development of Posttransplant Diabetes Mellitus: A Brazilian Single-Center, Observational Study

IntroductionPosttransplant diabetes mellitus (PTDM) is considered to be a serious complication of kidney transplantation that may reduce patient and graft survival. The immunosuppressant tacrolimus (TAC) increases the risk of developing PTDM.PurposeWe sought to estimate the risk of PTDM among renal transplant recipients treated with TAC, to identify other risk factors for PTDM, and to describe its consequences.MethodsWe retrospectively analyzed 413 recipients of ages ≥18 years who were free of diabetes before kidney transplantation. They were treated with TAC, cyclosporine (CyA), or sirolimus (SIR) plus steroid therapy with a minimum follow-up posttransplant of 6 months. PTDM was diagnosed according to American Diabetes Association guidelines.ResultsThe mean age was 42.3 years and 230 (55.7%) were male. The initial immunosuppression for 171 (41.4%) patients was TAC; 221 (53.5%), CyA; and 21 (5.1%), SIR. PTDM occurred in 85/413 (20.6%) of patients. The median time to PTDM development was 54 days posttransplant. The cumulative incidence of PTDM was 24.6% and 17.2% for TAC and CyA treatment groups, respectively. In the intention-to-treat analysis, the proportion of patients receiving TAC who developed PTDM was significantly higher than that of CyA (HR = 1.6 [1.01–2.42]; P = .04). The Kaplan-Meier method showed that 78.5% patients taking TAC were free of PTDM at 6 months compared with 88.8% taking CyA (P = .003). The other independent risk factors were body mass index (BMI; P < .0001); recipient age (P < .0001) and acute rejection episodes (AE; P = .01). Three-year actuarial graft survivals were 85.5% for PTDM patients compared with 93.3% for those without diabetes (P = .021); patient survivals, 88.9% and 96.7%, respectively (P = .017).ConclusionThe incidence of PTDM is associated with TAC use, recipient age, BMI, and ARE. Therefore, PTDM is an important risk factor for graft loss and mortality.