Randomized, double-blinded, controlled clinical trial of the effect of captopril, telmisartan and their combination on systemic inflammation of patients on hemodialysis

Abstract

To evaluate individual and combined effect of captopril and telmisartan on systemic inflammation markers of hemodialysis (HD) patients. Randomized, double-blinded, controlled clinical trial. Patients on HD at least 2 months, with arteriovenous fistula, were randomly allocated to groups: (1) captopril/placebo (N 13); (2) telmisartan/placebo (N 13); (3) captopril + telmisartan (N 12); or (4) placebo/placebo (N 12). During 3 months, patients received oral drugs as follows: captopril 50 mg/day, telmisartan 80 mg/day or placebo. Patients excluded if they had conditions or were on drugs potentially influencing on inflammation. Clinical and biochemical evaluations were performed monthly. Serum tumor necrosis factor alpha (TNFα), interleukin 6 (IL-6), and C-reactive protein (CRP) were measured at 0, 1 and 3 months. Baseline, demographic, clinical and biochemical variables were comparable between groups. Baseline versus final inflammatory markers were: captopril/placebo TNFα, 2.47 (0.1–4.5) versus 1.73 (0.3–3.8) pg/ml; IL-6, 17.03 (7.2–23) versus 7.90 (0.7–19) pg/ml; CRP, 4.21 (1.6–18) versus 5.9 (3.0–28) mg/l; telmisartan/placebo TNFα, 3.03 (2.3–4.6) versus 1.70 (1.2–2.0) pg/ml; IL-6, 14.10 (5.5–23) versus 9.85 (6.2–13) pg/ml; CRP, 5.74 (2.1–13) versus 10.60 (1.5–27) mg/l; captopril + telmisartan TNFα, 1.43 (0.7–5.4) versus 0.40 (0.1–2.1) pg/ml; IL-6, 10.05 (4.9–23) versus 4.00 (0.7–7.7) pg/ml (p < 0.05); CRP, 3.26 (0.7–12) versus 2.83 (0.6–6.5) mg/l; placebo/placebo TNFα, 3.13 (1.6–5.6) versus 1.64 (1.6–2.3) pg/ml; IL-6, 8.12 (5.4–16) versus 7.60 (2.4–15) pg/ml; CRP, 5.23 (1.9–16) versus 3.13 (1.5–18) mg/l. Monotherapy with captopril or telmisartan display a trend, but their combined treatment significantly decreased serum levels of IL-6. No remarkable changes on TNFα and CRP were observed.