Diabetes mellitus after kidney transplantation in Japanese patients: The Japan Academic Consortium of Kidney Transplantation study

Abstract

Objectives: To clarify the incidence rate of post-transplant diabetes mellitus and associated risk factors in Japanese kidney transplant recipients, and to explore which treatment components are most effective in reducing post-transplant diabetes mellitus.

Methods: We analyzed 849 Japanese non-diabetic adult recipients who had undergone living kidney transplantation and had received tacrolimus-based immunosuppression from 1996 to 2013 with a median follow-up of 5 years.

Results: In all, 127 patients developed post-transplant diabetes mellitus during the follow-up period. The incidence rate of post-transplant diabetes mellitus was 15.1% (95% confidence interval 12.7-17.5) at 5 years. Recipient age (hazard ratio 1.05, 95% confidence interval 1.05-1.06, P < 0.001 for every 5-year increase), obesity (hazard ratio 1.70, 95% confidence interval 1.06-2.73, P = 0.028), tacrolimus trough level at 2 weeks post-transplantation (hazard ratio 1.06, 95% confidence interval 1.03-1.09, P < 0.001 for a 1-ng/mL increase) and mycophenolate mofetil use (hazard ratio 0.46, 95% confidence interval 0.28-0.77, P = 0.003) were significant predictors of post-transplant diabetes mellitus. Estimated 5-year predicted incidence rate after adjusting for age and obesity was 9.4% for recipients with a low tacrolimus trough level, and receiving mycophenolate mofetil and 38.4% for recipients with a high tacrolimus trough level and not receiving mycophenolate mofetil.

Conclusions: Post-transplant diabetes mellitus is a common complication in Japan, similar to that in other Western countries. The present results show that an appropriate immunosuppressive regimen with a combination of tacrolimus and mycophenolate mofetil can reduce the likelihood of developing post-transplant diabetes mellitus. Clinical trials are required to confirm these findings.

Keywords: living kidney transplantation; mycophenolate mofetil; new onset diabetes mellitus; post-transplant diabetes mellitus; tacrolimus formulation.