Advantageous effects of immunosuppression with tacrolimus in comparison with cyclosporine A regarding renal function in patients after heart transplantation

Background: Nephrotoxicity is a serious adverse effect of calcineurin inhibitor therapy in patients after heart transplantation (HTX). Aim: In this retrospective registry study, renal function within the first 2 years after HTX in patients receiving de novo calcineurin inhibitor treatment, that is, cyclosporine A (CSA) or tacrolimus (TAC), was analyzed. In a consecutive subgroup analysis, renal function in patients receiving conventional tacrolimus (CTAC) was compared with that of patients receiving extended-release tacrolimus (ETAC). Methods: Data from 150 HTX patients at Heidelberg Heart Transplantation Center were retrospectively analyzed. All patients were continuously receiving the primarily applied calcineurin inhibitor during the first 2 years after HTX and received follow-up care according to center practice. Results: Within the first 2 years after HTX, serum creatinine increased significantly in patients receiving CSA (P. 0.0001), whereas in patients receiving TAC, change of serum creatinine was not statistically significant (P=not statistically significant [ns]). McNemar's test detected a significant accumulation of patients with deterioration of renal function in the first half year after HTX among patients receiving CSA (P=0.0004). In patients receiving TAC, no significant accumulation of patients with deterioration of renal function during the first 2 years after HTX was detectable (all P=ns). Direct comparison of patients receiving CTAC versus those receiving ETAC detected no significant differences regarding renal function between patients primarily receiving CTAC or ETAC treatment during study period (all P=ns). Conclusion: CSA is associated with a more pronounced deterioration of renal function, especially in the first 6 months after HTX, in comparison with patients receiving TAC as baseline immunosuppressive therapy.