Although the use of metformin for diabetes in kidney transplant recipients is uncommon, results of a recent study published in Clinical Transplantation indicate significantly lowered mortality rates, as well as less significant trends toward reduced graft failure and rejection.
Subjects were selected for study analysis using the Scientific Registry of Transplant Recipients (SRTR) data, which records demographic and clinical data on all transplant recipients, donors, and candidates in the United States; additional information was found by linking SRTR records to pharmaceutical claims data from Symphony Health Solutions.
Selected participants (N=14,144) had records of kidney transplantation between January 1, 2007, and December 31, 2013; were old enough for metformin treatment (≥10 years of age); had type 2 diabetes mellitus; and had available records showing pharmaceutical treatment with a diabetes medication in year 1 post-transplant.
Of the total study participants, 4.7% filled prescriptions for metformin post-transplant (n=665); when compared with diabetes treatment regimens without metformin, these participants showed significantly reduced malignancy-related, infection-related, and all-cause mortality rates. Nonsignificant reductions in cardiovascular mortality and graft failure and rejection were also identified in this group.
The study investigators concluded that although metformin-based treatment for diabetic kidney transplant was uncommon, it was not associated with elevated risk for adverse graft or patient outcomes. “Rather, metformin exposure was associated with reduced mortality and non-significant trends toward lower rates of rejection and graft loss.
While these findings warrant replication in additional studies, examination of linked national registry and pharmacy fill records is an efficient strategy for identifying uncommon treatments in transplant recipients that can confirm, extend, and provide hypotheses for gold standard, but costly, clinical trials.”
Vest LS, Koraishy FM, Zhang Z, et al. Metformin use in the first year after kidney transplant, correlates and associated outcomes in diabetic transplant recipients: a retrospective analysis of integrated registry and pharmacy claims data [published online May 31, 2018]. Clin Transplant. doi: 10.1111/ctr.13302