[Can angiotensin-converting enzyme inhibitor be used in chronic kidney disease patients with serum creatinine level greater than 266 micromol/L?].

OBJECTIVE

Angiotensin-converting enzyme inhibitor (ACEI) has been demonstrated to have protective effect for patients with mild to moderate chronic kidney disease (CKD). However, little evidence is available for the benefit or side-effects of ACEI in treating patients with more severe CKD. A prospective, randomized controlled trial was performed to evaluate the renal protective effect and safety of ACEI in patients whose serum creatinine (Scr) levels were higher than 265 micromol/L.

METHODS

168 CKD patients took benazepril for two months. 21 patients quitted the trial because of cough. The remaining 147 CKD patients were divided into two groups according to their Scr levels. Patients with Scr 133 - 265 micromol/L were included in group A (n = 55), and those with Scr 266-442 micromol/L were included in group B (n = 92). Furthermore, group B were divided randomly into two subgroups, B1 (n = 47) and B2 (n = 45). Benazepril was given (10 - 20 mg/d) as an intervention for group A and group B1. Additional calcium-channel antagonist and/or beta-blocker and/or vasodilator were used for blood pressure control in those two groups. Patients in group B2 served as controls who take calcium-channel antagonist and/or beta-blocker and/or vasodilator but not Benazepril. The target blood pressure is 125/75 mm Hg or less in all groups. All patients were followed for two years. Doubling of the baseline Scr level or end-stage renal disease with the need for dialysis was regarded as the major end point of the trial.

RESULTS

(1) The magnitude of mean arterial pressure reduction was comparable in group A [(12.90 +/- 3.21) mm Hg], group B1 [(13.36 +/- 4.27) mm Hg] and group B2 [(10.38 +/- 3.85) mm Hg]. There was no significant change among them (P > 0.05 in all). (2) The magnitude of urinary protein reduction (Delta) in group A [(0.52 +/- 0.29) g/24 h], group B1 [(0.50 +/- 0.26) g/24 h] were much higher than that in group B2 [(0.19 +/- 0.13) g/24 h] (P < 0.05), but there was no significant difference between group A and B1 (P = 0.94). (3) By the end of two years, the percentages of cases reaching the major end point in group A, group B1 and group B2 were 19.23%, 40.90% and 51.35% respectively. There was significant difference among the three groups (chi(2) = 12.14, upsilon = 2, P = 0.002). (4) After two years of treatment, the left ventricular mass indexes and the percentages of left ventricular hypertrophy in group A, group B1 and group B2 were all decreased significantly. There were no statistical differences among the three groups. (5) The incidence of ACEI related adverse reactions, such as rapid increase of Scr more than 30%, dry cough or hyperkalemia were not different among the three groups.

CONCLUSIONS

Benazepril slows the progression of CKD in patients with Scr higher than 266 micromol/L, it is safe in these patients.