Posttransplantation diabetes mellitus: a long-term retrospective cohort study

Posttransplantation diabetes mellitus (PTDM) is a serious complication of transplantation which is caused by immunosuppressive drugs and adversely affects the survival of the transplant recipient and the long-term survival of the graft. In this study, we assessed the incidence of PTDM and the factors associated with its development during long-term follow-up of renal transplant recipients. We also investigated the influence of PTDM on the cardiovascular risk (CVR) profile.

We retrospectively reviewed the records of the patients who underwent renal transplantation at our center between 1986 and January 2007. Diabetes was diagnosed according to American Diabetes Association criteria. The CVR factors were analyzed at the time of transplantation as well as at 1 and 3 years follow-up.

We included 136 nondiabetic transplant recipients. The PTDM incidences at 1, 3, 5, and 10 years were 9%, 12%, 13%, and 16.4%, respectively. The cumulative incidence during follow-up was 17.6%. On both univariate and multivariate analyses body mass index (BMI) was significantly associated with PTDM. Patients with BMI 25 = 30 kg/m(2) had an odds ratio [OR] of 3.53 (95% confidential interval [CI] 1.26-9.90; P = .017) and those with BMI >30 kg/m(2) had an OR of 4.58 (95% CI 1.4-14.01; P = .012). There were no significant differences in gender distribution, age, pretransplant dialysis period, acute rejection rate, or immunosuppressive regimens between patients with (n = 24) versus without (n = 112) PTDM.

The risk of PTDM increased continuously with time after transplantation. BMI was an independent predictor of PTDM. Among all of the risk factors for PTDM, obesity is the only modifiable risk factor before transplantation. PTDM was associated with a worse traditional CVR profile; a better control of CVR factors should be performed to prevent long-term morbidity and mortality in this population.