A randomized prospective comparison of nadolol, captopril with or without ticlopidine on disease progression in IgA nephropathy

Abstract

To determine if angiotensin converting enzyme inhibitors (ACEI) and antiplatelet agents have any added advantages over beta-blockers in preventing disease progression in IgA nephropathy (IgAN), 52 patients with IgAN with at least two features suggestive of progressive disease, namely, proteinuria >1 gm/day, mean blood pressure (MBP)>107 mmHg, serum creatinine 0.12-0.4 mmol/L and the presence of glomerulosclerosis and/or tubulointerstitial fibrosis on initial biopsy were randomized to receive nadolol (N), captopril (C) and captopril plus ticoplidine (CT). In hypertensive subjects, the dose N and C was adjusted to normalize MBP. In normotensive subjects the dose was adjusted to achieve a reduction of MBP of 5-10 mmHg. Five patients withdrew prematurely before reaching the end of the study period. The results after a minimal period of 3 years follow-up were available in the remaining 47 patients (n = 16, 12 and 19 in groups N, C and CT, respectively). Target of blood pressure (BP) treatment was achieved in all patients and the post-treatment MBP was comparable among the three groups. In C and CT, peripheral blood renin increased significantly while in CT, in vitro platelet aggregation decreased significantly following treatment. Urinary protein and albumin excretion decreased significantly in all treatment groups but there was no difference among the three groups. Progression of renal failure as measured by life table analysis of the percentage of patients with doubling of serum creatinine and by the slope of the reciprocal of serum creatinine (mean ± SEM: -0.021 ± 0.014; -0.016 ± 0.010 and -0.017 ± 0.008 for N, C and CT, respectively) and of glomerular filtration rate as measured by plasma disappearance of injected Cr 51EDTA over time (mean ± SEM: -0.556 ± 0.157, -0.739 ± 0.304 and -0.543 ± 0.274 for N, C and CT) were similar among the three groups. In this small comparative study, ACEI does not appear to be better than long-acting beta- blocker in retarding disease progression in patients with IgAN and ticlopidine confers no additional benefit.