Home glucometer monitoring markedly improves diagnosis of post renal transplant diabetes mellitus in renal transplant recipients

Background. Definitions of de novo posttransplant diabetes mellitus (PTDM) have varied widely in the renal transplant literature, and most have not used the American Diabetes Association (ADA) definition of diabetes (fasting plasma glucose [FPG] ≥126 mg/dl on two occasions, or a casual plasma glucose level >200 mg/dl). Most patients are monitored for PTDM by 12-hour FPG levels drawn for clinic visits. In contrast, we describe the diagnosis of PTDM by home glucometer monitoring. Methods. We screened 89 consecutive nondiabetic renal transplant recipients for PTDM by ADA criteria and home glucometer monitoring during the first 3 months posttransplant. Results. Of 23 patients with impaired fasting glucose levels of 111-126 mg/dl, 14 (61%) met ADA criteria for diabetes mellitus of based on home glucometer monitoring. The incidence of de novo PTDM was 31% during this period. Predictors of PTDM in a Cox proportional hazards model were race and acute rejection, with a trend towards BMI. Clinic visit FPG levels did not differ between PTDM and non-PTDM patients. All diagnoses were made based on prelunch or supper FPG >200 mg/dl. Conclusions. Overnight FPG are inadequate for diagnosis of PTDM. All renal transplant recipients with impaired FPG should, at minimum, have home FPG testing.