Effects of barnidipine in comparison with hydrochlorothiazide on endothelial function, as assessed by flow mediated vasodilatation in hypertensive patients

BACKGROUND. In hypertensive patients, endothelial dysfunction is associated with an increased incidence of cardiovascular events. Calcium-channel antagonists can reverse impaired endothelium-dependent vasodilation in different vascular districts, while conflicting results are found in the brachial artery. Aim. To investigate the effect of barnidipine in comparison with hydrochlorothiazide on endothelial function of hypertensives, as assessed by flow-mediated vasodilation (FMD) of the brachial artery. METHODS. Patients with mild to moderate hypertension (age range 26-67 years) were randomized to receive barnidipine or hydrochlorothiazide. A thorough clinical examination, including blood pressure (BP) measurement, was performed at randomization as well as after 6, 12 and 24 weeks. FMD and 24-h BP monitoring was performed at randomization, after 12 and 24 weeks. RESULTS. After 12 and 24 weeks of treatment, a significant reduction in clinic BP was observed in both groups. Furthermore, a significant reduction in 24-h SBP and DBP was observed in patients receiving barnidipine but not in those receiving diuretic. The percentage change in FMD was different between the two groups of patients treated with barnidipine (at 12 weeks +1.2 ± 2.2%, p = 0.023 and at 24 weeks +1.25 ± 3.15%, p = 0.16 from baseline) or with hydrochlorothiazide (at 12 weeks -1.0 ± 3.0. p = 0.09 and at 24 weeks -1.78 ± 2.9%, p = 0.015 from baseline). A significant difference in FMD changes between the two groups was confirmed by analysis of covariance (p = 0.031). CONCLUSIONS. In presence of a similar clinic BP reduction, an improvement of endothelial function was observed during treatment with barnidipine but not with hydrochlorothiazide, suggesting that the barnidipine may exert a favourable effect on endothelial dysfunction in hypertensive patients.