Blood pressure control in kidney transplant recipients: influence of immunosuppression

1. Disturbances of the blood pressure regulation, probably due to dysfunction of the autonomic nervous system, are well known complications in chronic renal failure. Haemodialysis and transplantation have been reported to ameliorate nerve dysfunction. 2. In this study, the function of the blood pressure control was investigated in kidney transplant recipients after longtime haemodialysis treated with ciclosporine A and tacrolimus and compared to healthy individuals. To investigate the influence of immunosuppression, the measurements were performed twice, at low and high whole blood concentrations of ciclosporine and tacrolimus. Besides ciclosporine, tacrolimus, azathioprine and prednisolone no other drugs were used in the group of kidney transplant recipients. 3. Kidney transplant recipients (KTR) treated with ciclosporine showed reduced blood pressure and heart rate responses to the cardiovascular stress tests (head-up tilt and cold pressure test) under basal conditions. Two hours after ciclosporine application, the differences in the responses to cardiovascular stress tests between KTR and controls were significantly more pronounced. 4. Patients with tacrolimus immunosuppression showed a similar blood pressure and heart rate response under basal conditions. Two hours after drug application, the blood pressure response following orthostatism and heart rate response to the cold pressure test were significantly higher in tacrolimus treated patients. 5. Our results indicate, that kidney transplant recipients still express an altered function of the blood pressure control. Furthermore, ciclosporine A and tacrolimus seem to contribute to dysfunction of the blood pressure regulation by their own. Tacrolimus immunosuppression does not seem to offer advantages concerning the function of the blood pressure control as compared to ciclosporine A.