Objectives: Cilnidipine is a calcium channel blocker that blocks both L and N-type calcium channels. L/N-type calcium channel blockers exhibit sympatholytic action and a renal protective effect via dilation of afferent and efferent arterioles of the renal glomerulus, and afford more potent protection against hypertension-related organ damage than L-type calcium channel blockers. Few studies, however, have directly compared the organ protective effects of L-type calcium channel blocker monotherapy and L/N-type calcium channel blocker monotherapy. This study compares the effects on renal and vascular endothelial functions and arterial stiffness of monotherapy regimens of amlodipine, an L-type calcium antagonist, and cilnidipine, in patients with essential hypertension.
Methods: Fifty patients with untreated essential hypertension were randomized to receive 5 mg of amlodipine (n = 25) or 10 mg of cilnidipine (n = 25) once daily in the morning for 24 weeks. The patients were evaluated before and after the therapy to assess changes in renal function, flow-mediated vasodilation (a parameter of vascular endothelial function), and brachial-ankle pulse wave velocity (a parameter of arterial stiffness).
Results: Before treatment, the above parameters showed no significant differences between groups. After treatment, urinary albumin excretion was decreased significantly in the cilnidipine group compared with the amlodipine group, and the decrease of brachial-ankle pulse wave velocity was significantly larger in the cilnidipine group than in the amlodipine group.
Conclusions: These results suggest that cilnidipine is more effective than amlodipine at improving renal function and arterial stiffness in patients with essential hypertension.