Impact of Hibiscus on Cardiovascular Disease Risk (PHYTOVAS)

Acute Impact of Hibiscus Sabdariffa Calyces (HSC) Extract Consumption on Blood Pressure, Vascular Function and Other Cardiovascular Risk Factors

Hibiscus sabdariffa calyces (HSC) extract is consumed in different parts of the world as a cold or hot drink and is available in the United Kingdom (UK) markets in different forms including tea bags. There is preliminary data that support the hypothesis that HSC extract consumption has beneficial effect on blood vessel health and blood pressure reduction. Hypertension, vascular dysfunction, inflammation and lipid abnormalities are all key modifiable risk factors of cardiovascular diseases (CVD), the leading causes of death throughout the world. In the PHYTOVAS (PHYTOchemicals and VAScular Function) study the effect of the acute consumption a potentially bioactive food extracts: Hibiscus sabdariffa calyces (HSC) compared with a matched control (water) on blood pressure and blood vessels function will be investigated after a high - fat mixed meal. This is with a view to determining the impacts of the extract on postprandial (after meal) blood pressure and other CVD risk factors. Results from the PHYTOVAS study could lead to identification of more dietary approaches that will contribute to CVD risk prevention and management.

Study Overview

• Status: Completed
• Conditions: Cardiovascular Diseases
• Intervention / Treatment: Dietary supplement: Hibiscus sabdariffa calyces extract as a cold drink

• Study Type: Interventional
• Enrollment (Actual): 25
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United Kingdom
  • Berkshire
    • Reading, Berkshire, United Kingdom, RG6 6AP
      • Department of Food and Nutritional Sciences, University of Reading,

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 30 years to 65 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: Male

Description

Inclusion Criteria:

• Male
• 30 - 65 years
• 1 to 10 % Cardiovascular disease risk in 10 years
• Not taking blood pressure medication
• Not having liver or kidney disease
• Not anaemic
• A signed consent form

Exclusion Criteria:

• Female
• <30 or > 65 years
• <1 or >10 % Cardiovascular disease risk in 10 years
• Taking blood pressure medication
• Having liver or kidney disease
• Anaemic
• Lack of signing consent form
• Vegan
• Individual with food allergy
• Sufferers of chronic illness

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Hibiscus sabdariffa calyces extract as a cold drink; Subjects are asked to consume 250 ml of Hibiscus calyces drink after a high fat breakfast	Dietary supplement: Hibiscus sabdariffa calyces extract as a cold drink; Other Names: Hibiscus flower tea; Hibiscus tea; Roselle
Placebo Comparator: Water; Subjects are asked to consume 250 ml of water after a high fat breakfast	Dietary supplement: Hibiscus sabdariffa calyces extract as a cold drink; Other Names: Hibiscus flower tea; Hibiscus tea; Roselle

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Change in baseline and hourly blood pressure	Baseline, hourly 4 times post baseline and then hourly for twelve hours at night

Secondary Outcome Measures

Outcome Measure	Time Frame
Change in Flow Mediated Vasodilation	Baseline, 2 and 4 hours post treatment
Change in blood lipids profile	Baseline and 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4 hours post treatment
Change in Inflammatory marker: C - reactive protein (CRP)	Baseline and 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4 hours post treatment
Change in plasma nitric oxide level	Baseline and 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4 hours post treatment
Change in serum total antioxidant capacity	Baseline and 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4 hours post treatment
Changes in serum or plasma glucose and insulin levels	Baseline and 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4 hours post treatment

Other Outcome Measures

Outcome Measure	Time Frame
Change in arterial stiffness measured by Pulse Wave Analysis (PWA)	Baseline, 2 and 4 hours post treatment
Pharmacokinetics of plasma anthocyanins and phenolic acids measured as Area Under the Concentration - Time Curve (AUC 0 - 4 hours for plasma)	Baseline and 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4 hours post treatment

Collaborators and Investigators

• Sponsor: University of Reading
• Investigators: Principal Investigator: Jeremy P.E. Spencer, B.Sc, PhD, University of Reading

Study record dates

Study Major Dates

• Study Start: January 1, 2014
• Primary Completion (Actual): August 1, 2014
• Study Completion (Actual): March 1, 2015

Study Registration Dates

• First Submitted: June 1, 2014
• First Submitted That Met QC Criteria: June 13, 2014
• First Posted (Estimate): June 17, 2014

Study Record Updates

• Last Update Posted (Estimate): September 7, 2015
• Last Update Submitted That Met QC Criteria: September 4, 2015
• Last Verified: September 1, 2015

More Information

Terms related to this study

• Keywords: Inflammation; Blood Pressure; Vascular Function; Hibiscus sabdariffa calyces; Cardiometabolic risk markers; Systemic antioxidant capacity
• Additional Relevant MeSH Terms: Cardiovascular Diseases
• Other Study ID Numbers: 13/40