Cost containment: coadministration of diltiazem with cyclosporine after heart transplantation.

Coadministration of diltiazem with cyclosporine (CsA) has been reported to alter the metabolism of CsA, resulting in increased blood concentration with potential nephrotoxicity if dosage is not adjusted. This report analyzes the cost saving resulting from use of diltiazem and CsA together and examines the impact on renal function. Sixty-nine heart transplant recipients (59 men, 10 women) were randomized to diltiazem (n = 32) or to no calcium blocker (n = 37). Age range was 18 to 58 years. All patients received CsA (titrated to a 12-hour trough serum level of 100 to 200 ng/ml), azathioprine, and prednisone. Diltiazem was begun at 30 mg three times daily increasing to 60 mg three times daily at 1 month, as tolerated. Renal function was assessed by serial measurements of serum creatinine. Parameters before and after starting diltiazem were compared by paired t-tests, and differences between group means by analysis of variance. CsA doses and levels were comparable at baseline in both groups. At 12 months, CsA dose requirement was 2.5 +/- 1.0 versus 5.9 +/- 3.2 mg/kg/day (diltiazem group versus no calcium blocker group; p less than or equal to 0.001) to achieve similar serum levels (96 +/- 51 versus 123 +/- 96 ng/ml; p = NS). This represents a 48% reduction in dose cost of CsA. The average cost of CsA for 2 to 4 months of therapy in a patient weighing 70 kg was reduced from $12,122 in the no calcium blocker group to $6,356 in the diltiazem group.(ABSTRACT TRUNCATED AT 250 WORDS)

RCT Entities:   Population Interventions Outcomes