In older and obese adults undergoing kidney transplantation, immunosuppression without the use of steroids is associated with a lower risk of posttransplant diabetes mellitus, suggests a study in Kidney Medicine (1).
The retrospective analysis included data on adult kidney-only transplant patients from 2005 to 2016 with Medicare billing claims, drawn from the US Renal Data System. Incidence of posttransplant diabetes was analyzed, including the impact of age and obesity (body mass index 30 kg/m2 or greater). The impact of immunosuppression was analyzed by inverse propensity weighting, with thymoglobulin (TMG) or alemtuzumab (ALEM) plus mycophenolic acid plus prednisone as the reference regimen.
Overall incidence of posttransplant diabetes was 12.7%. Incidence was higher in older patients: 16.7% for patients aged 55 years or older versus 10.1% in patients younger than 55. Obese patients were also at higher risk of posttransplant diabetes: 17.1% versus 10.9%.
Patients whose immunosuppressive regimen did not include steroids were less likely to develop posttransplant diabetes. Incidence was 8.4% in patients receiving TMG/ALEM with no prednisone and 9.7% for those receiving anti-interleukin 2 receptor antibodies with no prednisone compared to 13.1% for those receiving TMG/ALEM with triple therapy.
With adjustment for donor and recipient characteristics, TMG/ALEM without steroids was associated with a lower risk of posttransplant diabetes across groups. The adjusted hazard ratio (HR) was 0.63 in patients younger than 55 compared to 0.69 in older patients and 0.67 in obese patients compared to 0.69 in non-obese patients. In contrast, anti-interleukin 2 receptor antibodies with no steroid were protective only in older patients (HR 0.76) and non-obese patients (HR 0.63). Mammalian target of rapamycin inhibitor-based immunosuppression was associated with an increased rate of posttransplant diabetes, with an adjusted HR of 1.40.
Patients who develop diabetes mellitus after kidney transplantation are at risk of increased morbidity and mortality, especially older and obese patients. Previous evidence suggests that the choice of an immunosuppressive regimen might be a modifiable risk factor for posttransplant diabetes. This study of Medicare-insured kidney transplant recipients finds a lower risk of posttransplant diabetes in those receiving steroid-free immunosuppressive regimens.
Although the protective effect of steroid avoidance is apparent in both older and obese recipients, the effects of concomitant cell depletion may differ.
“These data support consideration of the risk of non-immune complications along with rejection risk when selecting immunosuppression regimens in kidney transplant recipients to minimize patient morbidity from immunosuppression associated side effects,” the authors state.
Reference
Axelrod DA, et al. Posttransplant diabetes mellitus and immunosuppression selection in older and obese kidney transplant recipients. Kidney Med [published online ahead of print October 22, 2021]. https://www.sciencedirect.com/science/article/pii/S259005952100220X.
