Conditions: Hypertension
Allocation: RANDOMIZED | Intervention model: PARALLEL
Enrollment: 45
Healthy volunteers: no

Brief summary:
Numerous anti-hypertensive drugs have been reported to be efficacious in reducing central arterial stiffness and these effects may contribute to improved outcomes in hypertensive patients. However, the results of several studies suggest that beta-blockers may actually increase arterial stiffness. In contrast, there is limited evidence to suggest that nebivolol, a third generation beta-blocker that augments release of vascular nitric oxide, reduces central arterial stiffness in hypertensive individuals. Unfortunately, only a few studies have addressed this issue and all of these studies relied on indirect, blood pressure dependent measures of arterial stiffness. In addition, none of these studies focused on middle-aged and older, obese hypertensives, a population with accelerated arterial stiffening and at risk for cardiovascular diseases. Thus, the potential utility of nebivolol as a therapy to reduce large artery stiffness, particularly among the latter population, remains unclear.

Detailed description:

Arms:
arm 1: Subjects will be provided with daily 5 mg of nebivolol for the first 2 weeks. Subjects receive additional daily doses of 10 mg nebivolol for the remainder of the study period. The dose remains at 5 mg per day, however, if BP falls below 110/70 during the first 2 weeks. Subjects will continue taking the drug during the 2-week follow-up period. arm 2: Subjects will receive weekly lifestyle counseling by a registered dietitian to ensure adequate progress and compliance. Sample menus, 14-days of meal plans, and grocery shopping lists are provided to each individual. Individuals were instructed to reduce their daily caloric intake by 500-1000 calories and to perform a minimum of 150 minutes per week of moderate-intensity physical activity or 3000 steps/day above baseline levels. The diet plan conformed to the Dietary Approach to Stop Hypertension dietary guidelines emphasizing low fat dairy products, fruits and vegetable and contained 55% calories as carbohydrates, 30% calories as fat, and 15% calories as protein. Sodium consumption was set at 2,400 mg/day for all subjects. arm 3: Subjects begin with 5 mg/day of nebivolol and increase to 10 mg/day if brachial blood pressure is greater than 120/80 mmHg during the first 2 weeks of therapy. Subjects also receive weekly lifestyle counseling by a registered dietitian to ensure adequate progress and compliance. Sample menus, 14-days of meal plans, and grocery shopping lists are provided to each individual. Individuals will be instructed to reduce their daily caloric intake by 500-1000 calories and to perform a minimum of 150 min/wk of moderate-intensity physical activity or 3000 steps/day above baseline levels. The diet plan conforms to the Dietary Approaches to Stop Hypertension dietary guidelines emphasizing low fat dairy products, fruits and vegetable and contains 55% calories as carbohydrates, 30% calories as fat, and 15% calories as protein with sodium consumption set at 2,400 mg/day for all subjects.

Interventions: intervention 1: Nebivolol intervention 2: Lifestyle Modification intervention 3: Nebivolol plus Lifestyle Modification
Intervention descriptions: intervention 1: None intervention 2: None intervention 3: None

Protocol document: