Blueberry Consumption Improves Vascular Function and Lowers Blood Pressure in Postmenopausal Women With Pre- and Stage 1-hypertension
Condition: Blood Pressure
MeSH terms: Hypertension
Study type: Interventional
Phase: Phase 2

Summary: 
      Cardiovascular disease (CVD) continues to be the leading cause of death in the U.S. Americans
      have been more concerned about their blood cholesterol levels and dietary cholesterol intakes
      rather than their overall cardiovascular health risk factors leading to CVD such as
      hypertension, vascular dysfunction, inadequate consumption of fruits and vegetables and
      physical activity. Statistics show that approximately 91% of individuals with CVD have
      vascular dysfunction which is attributed to endothelial and autonomic dysfunction leading to
      increased arterial stiffness.

      The investigators long-term goal is to provide feasible and effective dietary ways for pre-
      and stage 1- hypertensive individuals to normalize their blood pressure (BP), improve
      vascular function and thereby reducing their cardiovascular risk and enhancing the quality of
      life. Blueberries are a rich source of phenolic compounds and these compounds may play an
      important role in promoting cardiovascular health. Considering the strong possibility that
      phytochemicals present in blueberry work additively or synergistically, it would be ideal to
      investigate the cardioprotective effects of blueberry as a whole. The investigators overall
      objective to bring forth evidence that blueberry consumption will reduce BP and
      cardiovascular risk factors including endothelial dysfunction, arterial stiffness, and
      autonomic dysfunction in pre- and stage 1-hypertensive postmenopausal women. The
      investigators hypothesize that blueberry supplementation will improve vascular function and
      will lower blood pressure in postmenopausal women with pre-hypertension. The findings of this
      study will provide a foundation for disseminating feasible, safe approaches for preventing
      and combating hypertension at its early stage which does not require drug therapy.
    

Detailed description: 
      The purpose of this study is to examine the effects of 22 grams of freeze-dried blueberry
      intake on a daily basis for eight weeks in:

      The purpose of the study is to examine the effects of 22 grams of freeze-dried blueberry
      intake on a daily basis for eight weeks on arterial function and blood pressure in
      postmenopausal women with pre- and stage 1-hypertension. The specific aims of the study are:

        1. To investigate the extent to which daily consumption of 22 g blueberry drink-mix reduces
           blood pressure in individuals with pre- and stage 1-hypertension.

        2. To determine whether daily consumption of 22 g blueberry drink-mix will improve the
           autonomic control of blood pressure and heart rate in individuals with pre- and stage
           1-hypertension.

        3. To measure serum markers of oxidative stress to determine whether increased antioxidant
           defense is in part responsible for blueberry's vascular protective effects.
    

Intervention name(s): Freeze-dried Blueberry Powder; Placebo
Intervention type(s): Dietary Supplement; Dietary Supplement
Intervention description(s): 8 weeks of freeze-dried taken in two doses of 22g each per day.; 8 weeks of freeze-dried taken in two doses of 22g each per day.
Other intervention name(s): U.S. Highbush Blueberry Council
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Double (Participant, Investigator)
Primary purpose: Treatment
Keywords: Blood pressure; Arterial Stiffness; Blueberry Supplementation; Aortic Blood Pressure; Hypertension; Postmenopausal; Pulse Wave Velocity