Background: Increased resting heart rate (HR) contributes to higher cardiovascular risk. We have previously shown that a conventional beta-blocker (BB) metoprolol and a vasodilating BB nebivolol equally reduce brachial blood pressure (BP) and HR, only nebivolol reduces central (aortic) BP. However, recent short-term studies have proposed that baseline HR values as well as change in HR with BB may augment central BP. Therefore, the use of BBs as antihypertensive drugs remains controversial.
Purpose: We aimed to study whether baseline HR level determines the change in brachial and central BP in long-term BB therapy in hypertensive patients.
Methods: We conducted a randomized, double-blind study in 80 hypertensive patients, who received either nebivolol 5 mg or metoprolol succinate 50–100 mg daily for one year. We performed brachial and central BP measurements at baseline and at the end of the study. The patients in each treatment arm were then divided into subgroups by their baseline HR (<65 bpm and ≥65 bpm).
Results: After 1 year of treatment brachial BP was reduced in all subgroups. In patients with baseline HR <65 bpm there was no change in HR and central BP in the metoprolol group, whereas in these patients nebivolol significantly reduced HR and central systolic BP (130±15 vs. 120±14 mmHg; p<0.01) and pulse pressure (49±10 vs. 43±8 mmHg; p=0.01). In patients with baseline HR ≥65 bpm both, metoprolol and nebivolol reduced HR significantly, but there was a significant reduction in central systolic BP (136±17 vs. 125±11 mmHg; p<0.05) only in the nebivolol group.
Conclusion: Our study suggests that despite HR and brachial BP reduction with BBs there is no additional augmentation of central BP. Vasodilating BB nebivolol reduces brachial and central BP regardless of baseline HR level.