Effect of Grape Seed Extract on Blood Pressure

Effect of Grape Seed Extract High in Polyphenols on Blood Pressure in Subjects With Elevated Blood Pressure Levels

The purpose of this study is to determine whether an 8-week intervention with grape seed extract is effective in reducing daytime ambulatory blood pressure in male and postmenopausal female with elevated daytime blood pressure values.

Study Overview

• Status: Completed
• Conditions: Elevated Blood Pressure
• Intervention / Treatment: Dietary supplement: Grape seed extract; Dietary supplement: Microcrystalline cellulose (placebo)

Detailed Description

Background: High blood pressure is a major risk factor for morbidity and mortality from stroke, heart disease, and end-stage renal disease. Several studies have shown that dietary polyphenols derived from fruits and vegetables (including those from grape products) can lower blood pressure in both normotensive and hypertensive subjects.

Study objectives: Primary objective: To study, in subjects with elevated blood pressure levels, the effects of grape seed extract high in polyphenols, on daytime ambulatory systolic and diastolic blood pressure (SBP and DBP, respectively). Secondary objective: To explore mechanistic pathways responsible for the blood pressure lowering efficacy in case a blood pressure lowering effect is shown.

Study population: Each treatment group will consist of 35 men and postmenopausal women (35-75 years of age) with daytime SBP between 120 and 159 mmHg. The total number of subjects will be 70.

Study design: This study will have a randomized, double-blind, placebo-controlled parallel design with 2 treatments, a 1-week run-in period, and an 8-week intervention period. The 2 treatments will consist of placebo capsules and capsules with grape seed extract.

Study outcomes: Daytime ambulatory blood pressure (ABP) will be measured every 20 minutes for 2 x 12 hours at baseline and 2 x 12 hours at the end of intervention. Furthermore, before and after the intervention period, 24-hour urine will be collected and 2 blood samples will be taken in order to investigate mechanistic pathways and platelet function.

• Study Type: Interventional
• Enrollment (Actual): 70
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Netherlands
  • Vlaardingen, Netherlands, 3133 AT
    • Unilever R&D Vlaardingen

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 35 years to 75 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Male and postmenopausal female subjects in the age ≥ 35 and ≤ 75 at start of the study
• BMI ≥ 18.5 and ≤ 30.0 kg/m2
• Apparently healthy: no reported diseases that may affect study results and pre-selected blood parameters within normal range
• Informed consent signed
• Willing to refrain from supplements, food products, diets and drugs that may interfere with the outcomes of the study

Exclusion Criteria:

• Mean of 6-hour ambulatory SBP < 120 mmHg, > 159 mmHg and/or DBP > 99 mmHg
• 10-year risk mortality risk on CVD > 10% according to NHG standard M84. For subjects > 65 years of age and SBP ≥ 140 mmHg the study physician will assess eligibility
• Irregular pulse or pulse < 50 or > 100 bpm
• Intense exercise >10 h/w
• Reported weight loss/gain > 10% of body weight in the 6 month preceding pre-study examination
• The habit of smoking during the past year

Study Plan

How is the study designed?

Design Details

• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Triple

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Placebo Comparator: Placebo; Microcrystalline cellulose	Dietary supplement: Microcrystalline cellulose (placebo); Subjects will daily consume one capsule with microcrystalline cellulose for 8 weeks.
Active Comparator: Grape seed; Grape seed extract	Dietary supplement: Grape seed extract; Subjects will daily consume one capsule with grape seed extract for 8 weeks.; Other Names: Polyphenol

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Difference between treatment and placebo in changes from baseline of ambulatory systolic and diastolic blood pressure	8 weeks of intervention

Secondary Outcome Measures

Outcome Measure	Time Frame
Difference between treatment and placebo in changes from baseline of mechanistic markers in plasma and/or urine (vasoactive factors and markers of polyphenol metabolism) and platelet function (only measured in case of a relevant BP-lowering effect)	8 weeks of intervention

Collaborators and Investigators

• Sponsor: Unilever R&D
• Collaborators: University of Edinburgh
• Investigators: Principal Investigator: Rouyanne T Ras, Msc, Unilever R&D Vlaardingen

Study record dates

Study Major Dates

• Study Start: March 1, 2009
• Primary Completion (Actual): July 1, 2009
• Study Completion (Actual): July 1, 2009

Study Registration Dates

• First Submitted: March 24, 2009
• First Submitted That Met QC Criteria: March 24, 2009
• First Posted (Estimate): March 25, 2009

Study Record Updates

• Last Update Posted (Estimate): August 28, 2009
• Last Update Submitted That Met QC Criteria: August 27, 2009
• Last Verified: August 1, 2009

More Information

Terms related to this study

• Keywords: Blood pressure; Grape seed
• Additional Relevant MeSH Terms: Cardiovascular Diseases; Vascular Diseases; Hypertension; Physiological Effects of Drugs; Molecular Mechanisms of Pharmacological Action; Antineoplastic Agents; Protective Agents; Antineoplastic Agents, Phytogenic; Antioxidants; Grape Seed Extract
• Other Study ID Numbers: 08050V