Insulin requirement after a renal transplant in patients with type 2 diabetes: the choice of calcineurin inhibitors.

OBJECTIVES Hyperglycemia is a common adverse event of immunosuppressive drugs used in organ transplant. Because cyclosporine is less diabetogenic than tacrolimus is, cyclosporine may be preferred in patients with pre-existing diabetes mellitus type 2, to prevent insulin treatment after a transplant. PATIENTS AND METHODS From March 2005 to June 2011, adult renal transplant patients with pre-existing diabetes mellitus type 2, who were not treated with insulin before a transplant, were treated with cyclosporine in combination with mycophenolate mofetil and corticosteroids. For comparison, we used historical controls who were treated with tacrolimus instead of cyclosporine. RESULTS Of the 16 patients treated with cyclosporine, only 4 remained free of insulin treatment after a follow-up of least 1 year, compared with 2 of 12 patients who were treated with tacrolimus (25% vs 17%; P = .67). Almost all patients required insulin treatment within 2 months of the transplant, and patients required comparable doses of insulin at different times after the transplant in both groups. None of the baseline characteristics could sufficiently predict the need to start insulin treatment. CONCLUSIONS Cyclosporine cannot be preferred over tacrolimus to minimize either the chance of requiring insulin treatment posttransplant or the dosage of insulin in patients with pre-existing diabetes mellitus type 2.