Converting-enzyme inhibitor versus calcium antagonist in cyclosporine-treated renal transplants

Abstract

Converting-enzyme inhibitor versus calcium antagonist in cyclosporine-treated renal transplants. The influence of antihypertensive treatment on the long-term evolution of arterial pressure and renal function was studied in a prospective controlled trial conducted in renal transplant recipients treated by cyclosporine. Within six months after transplantation, patients were randomly allocated to treatment by the angiotensin-converting enzyme inhibitor, lisinopril (ACEI, alone or associated with frusemide; N = 14), or the calcium antagonist, nifedipine (CA, alone or associated with atenolol; N= 11). Glomerular filtration rate (TcDTPA clearance) and effective renal plasma flow (hippuran clearance) as well as 24-hour urinary excretion of electrolytes and albumin were estimated at about 1 and 2.5 years of follow-up. Before initiation of antihypertensive therapy, the two groups were similar with regards to mean arterial pressure (119 ± 2 vs. 120 ± 4 mm Hg), effective renal plasma flow (285 ± 26 vs. 248 ± 33 ml/min/1.73 m2) and glomerular filtration rate (59 ± 4 vs. 61 ± 8 ml/min/1.73 m2 in the ACEI and CA groups, respectively). Both ACEI and CA treatments were associated with no change in renal function, a similar change in mean arterial pressure (ACEI - 18 ± 3; CA -13 ± 5 mm Hg) and identical trough blood levels of cyclosporine. Urinary albumin excretion did not change significantly in any groups. Of interest, only in the ACEI group did filtration fraction significantly decrease (from 0.22 ± 0.01% to 0.19 ± 0.01% at final studies). These results indicate that in cyclosporine-treated transplant recipients, a satisfactory control of hypertension is obtained by chronic ACEI, which is as effective on arterial pressure as a combination of CA and atenolol. A consistent reduction of arterial pressure by either treatment seems to afford a similar degree of renal protection in long-term cyclosporine treated patients.