Renoprotective effect and cost-effectiveness of using benidipine, a calcium channel blocker, to lower the dose of angiotensin receptor blocker in hypertensive patients with albuminuria.

In hypertensive patients with chronic renal disease, angiotensin receptor blockers (ARBs) are among the first-line drugs, and calcium channel blockers (CCBs) are recommended as a second line. We examined the effects of two therapeutic strategies using ARBs and benidipine, a CCB, on blood pressure (BP), urinary albumin excretion (UAE), and cost-effectiveness in hypertensive patients with albuminuria. Patients whose BP was 140/90 mmHg or higher despite treatment with low- or medium-dose ARBs were assigned randomly to two groups. In Group A (n=14), the ARB dose was maximized and then benidipine was added until BP targets were reached (<130/85 mmHg). In Group B (n=18), benidipine was administered first and then the ARB dose was increased until BP targets were reached. The BP targets were achieved by ARB alone in 36% of Group A patients and by the addition of benidipine in 83% of Group B patients. Finally, BP decreased in each group, reaching the targets in 93% of Group A patients and 94% of Group B patients after a 4-month therapeutic period. UAE was decreased in both groups after a 4-month therapeutic period compared to the allocation period (-33+/-6% in Group A, -31+/-6% in Group B; p<0.001, respectively). The monthly drug cost was higher (11,426+/-880 vs. 8,955+/-410 yen, p=0.012) and the cost-effectiveness of antihypertensive treatment was lower (p=0.003) in Group A than in Group B. We conclude that the addition of benidipine to low- or medium-dose ARB is, in light of the renal protection and the cost-effectiveness of this approach, a useful therapeutic strategy for controlling BP in hypertensive patients with albuminuria.