Background: The incidence of new-onset posttransplant diabetes mellitus (PTDM) is increased in renal transplant patients treated with tacrolimus.
Methods: We retrospectively analyzed fasting plasma glucose and HbA1c levels as well as the dose of glucose-lowering agents in 34 renal transplant patients converted from tacrolimus to cyclosporine (CsA) for PTDM. Diabetes was defined according to current guidelines as repeated fasting plasma glucose (FPG) levels > or =126 mg/dL.
Results: At conversion, 11 patients received insulin, 5 received oral agents, and 18 had no glucose-lowering therapy. Fasting plasma glucose levels decreased from 146 +/- 64 mg/dL at conversion to 111 +/- 26 mg/dL at 3 months and 104 +/- 21 mg/dL at 12 months (P < .001). HbA1c levels decreased from 6.8 +/- 0.8% at conversion to 6.0 +/- 0.6% at 12 months (P = .001). Insulin was stopped in 3, the dose reduced in 7, and remained stable in 1 of the patients. The average daily insulin dose among these patients was reduced from 31 +/- 17 units at conversion to 13 +/- 12 units at 12 months (P < .05). There was no significant change in the number of patients treated with oral glucose-lowering agents. Diabetes reversed (fasting plasma glucose < or = 125 mg/dL without glucose-lowering therapy) in 44% (95% confidence interval, 23% to 64%) of patients during the first year after conversion (P < .001). Graft function, blood pressure, and lipid levels remained stable after conversion but the proportion of patients receiving lipid-lowering therapy increased from 18% to 49% (P < .01).
Conclusions: Conversion from tacrolimus to CsA for PTDM was associated with a marked improvement in glucose metabolism and frequent reversal of diabetes.