The Association Between Variability in Tacrolimus Trough Levels and Posttransplant Diabetes Mellitus in Thai Kidney...

Tacrolimus (TAC) trough-level variability has been associated with patient outcomes and renal graft survival. However, its relationship with posttransplant diabetes mellitus (PTDM) remains unclear. This study aims to evaluate the association between the coefficient of variation (CV) of TAC (TAC-CV) and the incidence of PTDM within the first year after kidney transplantation (KT).

A multicenter retrospective study was conducted on 516 Thai KT patients who received TAC-based immunosuppressive regimens from 2011 to 2020, with a 1-y post-KT follow-up period. TAC-CV was calculated for the 0-12 mo post-KT period, and optimal cutoff values were determined using receiver operating characteristic analysis.

Of the 516 patients, 208 (40.31%) developed PTDM, whereas 308 (59.69%) did not during the first year post-KT. Significant associations were found between TAC-CV and PTDM throughout the study period (P < 0.001). The optimal CV cutoff values were identified as 36% (at 0-3 and 0-6 mo), 23% (at 6-12 mo), and 33% (at 0-12 mo) post-KT. High TAC-CV was strongly associated with an increased risk of PTDM during the first year post-KT.

These findings suggest that TAC-CV may serve as a valuable marker for identifying patients at high risk of PTDM and may aid in its prevention and effective management in KT recipients.