Abstract
A 12-month, multicenter (57 clinical institutions), randomized, open-labeled trial was undertaken to compare the efficacy of the angiotensin II receptor antagonist losartan and the calcium channel blocker amlodipine in patients with proteinuric chronic kidney disease (CKD) and hypertension. A total of 117 patients (79, chronic glomerulonephritis; 14, diabetic nephropathy; 24, other CKD) were randomly allocated into two treatment groups. Losartan and amlodipine exerted the same efficacy for blood pressure (BP) control; however, losartan significantly reduced the 24-h urinary protein excretion at months 3, 6, and 12, with the reduction of 20.7%, 35.2%, 35.8%, whereas amlodipine did not change the amount of proteinuria over the 12-month study period. When patients were stratified into groups according to the level of BP control at 3 months, the reduction in urinary protein excretion by losartan was evident in the group for which a BP of <140/90 mmHg was achieved, as well as in the group for which the goal BP (<130/85 mmHg) for treatment of CKD was not achieved. When patients were stratified according to baseline urinary protein excretion, those with ≥2 g/day showed a reduction in proteinuria by losartan of 23.3%, 39.4%, and 47.9% at months 3, 6, and 12, and those with <2 g/day showed a reduction of 18.5% and 31.2% at months 3 and 6, respectively. No fatal adverse events were experienced in either drug group. We conclude that losartan reduced proteinuria in patients with CKD and hypertension. This positive effect may contribute to the renal protective benefit of losartan, and is beyond the magnitude of BP control. (Hypertens Res 2004; 27: 21-30)
