Introduction:
New onset diabetes mellitus after kidney transplantation (NODAT), also referred to as post-transplantation diabetes mellitus (PTDM) is a common but serious metabolic complication of kidney transplantation. It is associated with poor patient and graft survival. Tacrolimus, a strong immunosuppressant, used for maintenance immunosuppression, reduces acute rejection rates but increases the risk of NODAT. Higher trough levels of tacrolimus during the first month after transplantation have been found to be a significant risk factor for the development of NODAT. The aim of this study was to identify the association between tacrolimus trough levels during the first year after kidney transplantation and to determine the incidence of NODAT.
Methods:
A retrospective study was done in a tertiary level transplant center of Nepal in September 2024. The medical records of living-donor kidney transplant recipients of ages >18 years who were free of diabetes before kidney transplantation and underwent kidney transplantation in between August 2022 and July 2023 were included in the study.The medical records were followed for 12 months after transplantation. Data regarding recipient and donor age, recipient and donor gender, dialysis method, body mass index, Human leukocyte Antigen (HLA) mismatches, induction and maintenance immunosuppression, fasting blood sugar level, incidence of acute rejection and delayed graft function, tacrolimus trough blood level and corresponding tacrolimus daily doses and concentration dose ratios (CDR) were collected. NODAT was defined as at least 2 fasting blood glucose values >126 mg/dl after 3 months post transplantation according to World Health Organization (WHO) criteria.
Results:
A total of 77 patients were included in the study. The mean age was 34.08±9.86 years and 59 (76.6%) were males. The induction immunosupprssion was anti-thymocyte globulin in more than 95% cases. Maintenance immunosuppresssion was a triple immunosuppression regimen consisting of tacrolimus, mycophenolate mofetil (MMF) and prednisone in all patients. The median time to NODAT diagnosis was 6 months (3-12 months). Nine patients developed NODAT giving the incidence of first year NODAT of 11.69%. Thirteen (16.88%) patients were found to have prediabetes before tranasplant; 5 of them later developed transient hyperglycemia and 1 developed NODAT. Transient hyperglycemia was found in 24 (31.16%) patients; 5 of them later developed NODAT and the hyperglycemia in the remaining 19 patients resolved within 3 months. Of the 9 patients with NODAT, 5 (55.56%) had history of transient hyperglycemia. Patients with NODAT showed significantly higher age, BMI, first tacrolimus blood level >10ng/ml and first tacrolimus CDR. There was no significant difference in the acute rejection episodes,total steroid doses, overall graft and patient survival in patients with and without NODAT. After logistic regression analysis, age and first tacrolimus blood level remain significant risk factors for developing NODAT.
Conclusions:
In our population, the incidence of NODAT in the first year after kidney transplantation was 11.69%. Higher initial tacrolimus blood levels >10 ng/ml were associated with the higher risk of development of NODAT especially in patients >40 years of age and/or who are overweight. Kidney transplant recipients who develop NODAT maintain a high CDR of tacrolimus.
I have no potential conflict of interest to disclose.
I did not use generative AI and AI-assisted technologies in the writing process.