ABSTRACT
OBJECTIVE: To determine the effects of two beta-blockers, nebivolol and bisoprolol, on endothelial function in newly diagnosed hypertensive patients. METHODS: Twenty-five hypertensive patients with a mean (+/- SD) age of 45.3+/-11.5 years were randomly assigned to receive either nebivolol or bisoprolol for eight weeks in an open-label, crossover design. Flow-mediated endothelial-dependent vasodilation (FMD) was measured at baseline and after each eight-week treatment period. At the end of each treatment period, 24 h ambulatory blood pressure (BP) monitoring was performed. RESULTS: The effect of the two beta-blockers on BP was similar. The mean FMD before initiation of treatment was 4.14+/-3.55%. After treatment with nebivolol, FMD increased to 8.99+/-4.21%, with a statistically significant difference from baseline (P<0.001). The effect of bisoprolol treatment on FMD was not as dramatic (3.72+/-6.84%), with no statistically significant difference from baseline. Comparing FMD after each therapeutic regimen, nebivolol treatment resulted in a marked increase in the reactivity of the brachial artery (ie, improvement of endothelial function) compared with bisoprolol treatment (P<0.001). CONCLUSION: Nebivolol treatment of untreated hypertensive patients led to a significant improvement in endothelial function compared with bisoprolol treatment, despite the similar effect on BP with either therapeutic agent.
