Flavonoids, Blood Pressure and Blood Vessel Function
Condition: Cardiovascular Disease Risk Reduction
MeSH terms: Cardiovascular Diseases
Study type: Interventional

Summary: 
      The primary aim of this placebo-controlled study is to determine whether flavonoids
      beneficially affect markers of cardiovascular disease risk in healthy subjects at elevated
      cardiovascular risk.

      The underlying mechanisms of action of flavonoids will be assessed on blood biomarkers and we
      will assess the effects of the food matrix, and aspects of isoflavone metabolism.
    

Detailed description: 
      The study population will be healthy males (aged 50-75 years) at elevated risk of
      cardiovascular (CV) disease.

      A target of 60 participants will be required to complete the study and a total of 70 subjects
      will be targeted (n=70 subjects * ~85% anticipated completion rate = 60 subjects to complete
      the study).

      This placebo-controlled study will test the relative efficacy of 4 different flavonoid
      sub-classes ((i) flavan-3-ol, (ii) anthocyanin, (iii) flavanone and (iv) isoflavone).

      Accordingly, subjects will be randomised to one of the four flavonoid study groups ((i) to
      (iv) outlined above), and then will consume each of the following treatments in random order:

        1. dietary flavonoid + placebo supplement

        2. placebo food + commercially available/produced flavonoid supplement

        3. placebo food + placebo supplement

      Additionally, an isoflavone metabolite will be fed to establish potential vascular effects.

      Each sub-class will be assessed separately and a 1 week wash-out period between treatments
      will be observed.

      At each assessment visit, vascular function will be assessed pre- and post-intervention, with
      subsequent assessments made to coincide with anticipated peak plasma concentrations.

      Dietary intake will be monitored during the study and participants will be required to adhere
      to a range of dietary and lifestyle restrictions within 3 days of each assessment to reduce
      potential confounding of the data assessment of interest.

      A standard battery of vascular function tests will be performed on all intervention groups,
      with each assessment visit performed in an identical manner.
    

Intervention name(s): Flavanone - supplement; Flavanone - food; Flavanone - placebo; Isoflavone - supplement; Isoflavone - food; Isoflavone - placebo; Isoflavone - metabolite supplement; Flavan-3-ol - supplement; Flavan-3-ol - food; Flavan-3-ol - placebo; Anthocyanin - supplement; Anthocyanin - food; Anthocyanin - placebo
Intervention type(s): Dietary Supplement; Other; Other; Dietary Supplement; Other; Other; Dietary Supplement; Dietary Supplement; Other; Other; Dietary Supplement; Other; Other
Intervention description(s): acute single optimal dose; acute single dose; acute single dose (flavanone free); acute single optimal dose; acute single optimal dose; acute single dose (isoflavone free); acute single optimal dose of commercial product; acute single optimal dose; acute single optimal dose; acute single dose (flavan-3-ol free); acute single optimal dose; acute single optimal dose; acute single dose (anthocyanin free)
Allocation: Randomized
Intervention model: Factorial Assignment
Masking: Triple (Participant, Investigator, Outcomes Assessor)
Primary purpose: Basic Science
Keywords: flavonoids; vascular function; randomised controlled trial; placebo controlled