Impact of Hibiscus on Cardiovascular Disease Risk (PHYTOVAS)

September 4, 2015 updated by: Julie Lovegrove, University of Reading

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

Status

Indicates the current recruitment status or the expanded access status.
Completed

Conditions

Conditions

The disease, disorder, syndrome, illness, or injury that is being studied. On ClinicalTrials.gov, conditions may also include other health-related issues, such as lifespan, quality of life, and health risks.

Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.

Study Type

Study Type

Describes the nature of a clinical study. Study types include interventional studies (also called clinical trials), observational studies (including patient registries), and expanded access.
Interventional

Enrollment (Actual)

Enrollment

The number of participants in a clinical study. The "anticipated" enrollment is the target number of participants that the researchers need for the study.
25

Phase

Phase

The stage of a clinical trial studying a drug or biological product, based on definitions developed by the U.S. Food and Drug Administration (FDA). The phase is based on the study's objective, the number of participants, and other characteristics. There are five phases: Early Phase 1 (formerly listed as Phase 0), Phase 1, Phase 2, Phase 3, and Phase 4. Not Applicable is used to describe trials without FDA-defined phases, including trials of devices or behavioral interventions.
  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

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

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Eligibility Criteria

The key requirements that people who want to participate in a clinical study must meet or the characteristics they must have. Eligibility criteria consist of both inclusion criteria (which are required for a person to participate in the study) and exclusion criteria (which prevent a person from participating). Types of eligibility criteria include whether a study accepts healthy volunteers, has age or age group requirements, or is limited by sex.

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

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

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

Arms and Interventions

Participant Group / Arm

Participant Group / Arm

A group or subgroup of participants in a clinical trial that receives a specific intervention/treatment, or no intervention, according to the trial's protocol.
Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.
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

Primary Outcome Measures

In a clinical study's protocol, the planned outcome measure that is the most important for evaluating the effect of an intervention/treatment. Most clinical studies have one primary outcome measure, but some have more than one.
Outcome Measure
Time Frame
Change in baseline and hourly blood pressure
Time Frame: Baseline, hourly 4 times post baseline and then hourly for twelve hours at night
Baseline, hourly 4 times post baseline and then hourly for twelve hours at night

Secondary Outcome Measures

Secondary Outcome Measures

In a clinical study's protocol, a planned outcome measure that is not as important as the primary outcome measure for evaluating the effect of an intervention but is still of interest. Most clinical studies have more than one secondary outcome measure.
Outcome Measure
Time Frame
Change in Flow Mediated Vasodilation
Time Frame: Baseline, 2 and 4 hours post treatment
Baseline, 2 and 4 hours post treatment
Change in blood lipids profile
Time Frame: Baseline and 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4 hours post treatment
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)
Time Frame: Baseline and 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4 hours post treatment
Baseline and 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4 hours post treatment
Change in plasma nitric oxide level
Time Frame: Baseline and 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4 hours post treatment
Baseline and 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4 hours post treatment
Change in serum total antioxidant capacity
Time Frame: Baseline and 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4 hours post treatment
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
Time Frame: Baseline and 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4 hours post treatment
Baseline and 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4 hours post treatment

Other Outcome Measures

Other Outcome Measures

For clinical trials, a planned measurement described in the protocol that is used to determine the effect of an intervention/treatment on participants. For observational studies, a measurement or observation that is used to describe patterns of diseases or traits, or associations with exposures, risk factors, or treatment. Types of outcome measures include primary outcome measure and secondary outcome measure.
Outcome Measure
Time Frame
Change in arterial stiffness measured by Pulse Wave Analysis (PWA)
Time Frame: Baseline, 2 and 4 hours post treatment
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)
Time Frame: Baseline and 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4 hours post treatment
Baseline and 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4 hours post treatment

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Sponsor

The organization or person who initiates the study and who has authority and control over the study.
University of Reading

Investigators

Investigators

A researcher involved in a clinical study. Related terms include site principal investigator, site sub-investigator, study chair, study director, and study principal investigator.
  • Principal Investigator: Jeremy P.E. Spencer, B.Sc, PhD, University of Reading

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start

Study Start

The actual date on which the first participant was enrolled in a clinical study. The "anticipated" study start date is the date that the researchers think will be the study start date.
January 1, 2014

Primary Completion (Actual)

Primary Completion

The date on which the last participant in a clinical study was examined or received an intervention to collect final data for the primary outcome measure. Whether the clinical study ended according to the protocol or was terminated does not affect this date. For clinical studies with more than one primary outcome measure with different completion dates, this term refers to the date on which data collection is completed for all the primary outcome measures. The "anticipated" primary completion date is the date that the researchers think will be the primary completion date for the study.
August 1, 2014

Study Completion (Actual)

Study Completion

The date on which the last participant in a clinical study was examined or received an intervention/treatment to collect final data for the primary outcome measures, secondary outcome measures, and adverse events (that is, the last participant's last visit). The "anticipated" study completion date is the date that the researchers think will be the study completion date.
March 1, 2015

Study Registration Dates

First Submitted

First Submitted

The date on which the study sponsor or investigator first submitted a study record to ClinicalTrials.gov. There is typically a delay of a few days between the first submitted date and the record's availability on ClinicalTrials.gov (the first posted date).
June 1, 2014

First Submitted That Met QC Criteria

First Submitted That Met QC Criteria

The date on which the study sponsor or investigator first submits a study record that is consistent with National Library of Medicine (NLM) quality control (QC) review criteria. The sponsor or investigator may need to revise and submit a study record one or more times before NLM's QC review criteria are met. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
June 13, 2014

First Posted (Estimate)

First Posted

The date on which the study record was first available on ClinicalTrials.gov after National Library of Medicine (NLM) quality control (QC) review has concluded. There is typically a delay of a few days between the date the study sponsor or investigator submitted the study record and the first posted date.
June 17, 2014

Study Record Updates

Last Update Posted (Estimate)

Last Update Posted

The most recent date on which changes to a study record were made available on ClinicalTrials.gov. There may be a delay between when the changes were submitted to ClinicalTrials.gov by the study's sponsor or investigator (the last update submitted date) and the last update posted date.
September 7, 2015

Last Update Submitted That Met QC Criteria

Last Update Submitted That Met QC Criteria

The most recent date on which the study sponsor or investigator submitted changes to a study record that are consistent with National Library of Medicine (NLM) quality control (QC) review criteria. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
September 4, 2015

Last Verified

Last Verified

The most recent date on which the study sponsor or investigator confirmed the information about a clinical study on ClinicalTrials.gov as accurate and current. If a study with a recruitment status of recruiting; not yet recruiting; or active, not recruiting has not been confirmed within the past 2 years, the study's recruitment status is shown as unknown.
September 1, 2015

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

Other Study ID Numbers

Identifiers or ID numbers other than the NCT number that are assigned to a clinical study by the study's sponsor, funders, or others. These numbers may include unique identifiers from other trial registries and National Institutes of Health grant numbers.
  • 13/40

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

Cookie Settings

We use cookies to ensure that we give you the best experience on our website. For more details carefully read our Privacy and Cookies Policy. ...>>>You can change your preferences or withdraw your consent at any time by deleting the cookies from your website or computer as described in the policy. Please accept it and choose your preferences by ticking the corresponding boxes in the "Manage Settings" section below. Please carefully read our Terms of Service before you proceed with using any part of this website.
«Manage Settings