Studies on effects of calcineurin inhibitor withdrawal on arterial distensibility and endothelial function in renal transplant recipients1

Whether withdrawal of calcineurin inhibitors has a beneficial effect on disturbed endothelial function and large artery distensibility in renal transplant recipients is not clear. We studied the effects of cyclosporine A (CsA) withdrawal on arterial compliance and endothelium-dependent flow-mediated vasodilatation (FMD) in a prospective, randomized trial; 24 renal transplant recipients receiving mycophenolate mofetil were randomized to withdrawal (n=12) or continuation of CsA (n=12). At baseline and after 6 months, carotid and brachial artery distensibility coefficients and brachial FMD were measured. Brachial distensibility coefficients increased in both groups (withdrawal: 11.1+/-1-14.9+/-2 10(-3)/kPa, continuation: 10.7+/-1-15.2+/-3 10(-3)/kPa, P<0.05, respectively). However, there was no significant effect of treatment on carotid artery distensibility coefficients, FMD, or graft function. Withdrawal of CsA failed to improve carotid artery distensibility or brachial FMD in patients after renal transplantation. Our data indicate that CsA treatment does not contribute significantly to endothelial dysfunction observed in renal transplant recipients.