High impact of rejection therapy on the incidence of post-transplant diabetes mellitus after kidney transplantation

Background Although major risk factors for post-transplant diabetes (PTDM) after kidney transplantation have been identified, a systematic study on the impact of rejection and rejection therapy is missing so far. Methods Five hundred and twenty-six kidney transplant recipients transplanted in the years 2000-2007 were included. PTDM was defined according to WHO guidelines, and patients' data were compared with special attention to protocol and for cause biopsies and rejection therapies. Survival analyses were made for graft loss and patient death. Results 16.7% of all patients developed PTDM. Among common risk factors as higher age, body mass index (BMI), and others, the factor "acute cellular rejections" was comparably most relevant with a hazard ratio of 3.7. Consequently, antirejective treatment with steroid pulses and conversion to tacrolimus was the factor with the highest relative risk for the onset of PTDM (RR 3.5). PTDM itself had no impact on graft or patients' survival, but the decreased graft survival in PTDM patients was dominantly influenced by the higher frequency of acute cellular rejections, and patients' survival was reduced due to higher age. Conclusion Based upon a higher rate of acute rejections (AR), the necessity of frequent antirejective treatments was more relevant for the induction of PTDM than age or BMI.