Blood Pressure Lowering Effects of Grape Juice
|First Received Date ICMJE||March 13, 2006|
|Last Updated Date||June 16, 2009|
|Start Date ICMJE||March 2006|
|Primary Completion Date||Not Provided|
|Current Primary Outcome Measures ICMJE
||Blood pressure measured by 24-hour recorder [ Time Frame: 8 weeks ] [ Designated as safety issue: No ]|
|Original Primary Outcome Measures ICMJE
||Blood pressure measured by 24-hour recorder|
|Change History||Complete list of historical versions of study NCT00302809 on ClinicalTrials.gov Archive Site|
|Current Secondary Outcome Measures ICMJE
|Original Secondary Outcome Measures ICMJE
|Current Other Outcome Measures ICMJE||Not Provided|
|Original Other Outcome Measures ICMJE||Not Provided|
|Brief Title ICMJE||Blood Pressure Lowering Effects of Grape Juice|
|Official Title ICMJE||Effect of Concord Grape Juice on Blood Pressure and Vascular Function in Subjects With Pre-Hypertension and Stage 1 Hypertension|
Recent studies suggest that a diet rich in fruit and vegetables can lower blood pressure, and a number of lines of evidence suggest that grape products may have such an effect. The purpose of this study is to determine whether consuming grape juice lowers blood pressure in individuals with pre-hypertension or stage I hypertension.
Elevated blood pressure (BP) is among the most common and important risk factors for atherosclerosis. A number of non-pharmacological therapies have successfully been applied to prevent the development of elevated BP or reduce elevated BP. For example the DASH Study showed that a diet rich in fruits, vegetables and low fat dairy products, and reduced in saturated fat, total fat and cholesterol, substantially lowered blood pressure in normotensive and hypertensive individuals.
Within the past three years a number of small clinical trials have suggested suggest that drinking purple grape juice for a period of 6-12 weeks may lower blood pressure individuals with elevated blood pressure. Other clinical trials have shown that Concord grape juice improves the function of the vascular endothelium, possibly providing an explanation for the beneficial effect. However, there is a need for a prospective, controlled study to determine whether grape juice has a beneficial effect on blood pressure.
The present study will compare the effect of drinking Concord purple grape juice (7 ml/kg or about 16 oz/day for a 70 kg person) and the effect of calorie-matched placebo on 24-hour ambulatory blood pressure, blood pressure reactivity, and vascular function in men and women in the category of "pre-hypertension" (defined as blood pressure greater than 120/80, but less than 149/89 mmHg and Stage 1 hypertension (defined as blood pressure greater than 140/90, but less than 160/100). This study will specifically recruit patients with systolic blood pressure of 130-159 mmHg or diastolic blood pressure of 85-99 mmHg. The study will be double blind and have a crossover design with the order of treatment randomized (grape juice first or placebo first). A dietician will provide all subjects with formal instruction in a low salt diet, which is the current recommended initial therapy for patients with Stage 1 hypertension.
After a 1-week run-in period, subjects will consume each beverage for 8 weeks with a 4-week rest period between treatments. Blood pressure will be measured before and after each treatment period using a 24-hour ambulatory blood pressure recording. After each treatment period, we will measure changes in blood pressure induced by psychological challenge (mental arithmetic and computer tasks) and by the cold pressor test. In order to gain insight into the potential mechanisms of benefit, we will also examine the effects of beverage consumption on endothelial function, stiffness of the central aorta, fasting glucose and insulin, body weight, and markers of systemic inflammation, including CD40 ligand and C-reactive protein. Finally, we will store plasma samples for future investigation of other potential effects of grape juice on the cardiovascular system.
We hypothesize that Concord grape juice will have favorable effects on blood pressure compared to placebo.
|Study Type ICMJE||Interventional|
|Study Phase||Not Provided|
|Study Design ICMJE||Allocation: Randomized
Endpoint Classification: Efficacy Study
Intervention Model: Crossover Assignment
Masking: Double Blind (Subject, Caregiver, Investigator, Outcomes Assessor)
Primary Purpose: Treatment
|Intervention ICMJE||Dietary Supplement: Concord Grape Juice
Approximately 16 oz of grape juice or placebo
|Study Arm (s)||Not Provided|
|Publications *||Dohadwala MM, Hamburg NM, Holbrook M, Kim BH, Duess MA, Levit A, Titas M, Chung WB, Vincent FB, Caiano TL, Frame AA, Keaney JF Jr, Vita JA. Effects of Concord grape juice on ambulatory blood pressure in prehypertension and stage 1 hypertension. Am J Clin Nutr. 2010 Nov;92(5):1052-9. Epub 2010 Sep 15.|
* Includes publications given by the data provider as well as publications identified by ClinicalTrials.gov Identifier (NCT Number) in Medline.
|Recruitment Status ICMJE||Completed|
|Estimated Enrollment ICMJE||60|
|Completion Date||May 2009|
|Primary Completion Date||Not Provided|
|Eligibility Criteria ICMJE||
|Ages||21 Years to 75 Years|
|Accepts Healthy Volunteers||Yes|
|Contacts ICMJE||Contact information is only displayed when the study is recruiting subjects|
|Location Countries ICMJE||United States|
|NCT Number ICMJE||NCT00302809|
|Other Study ID Numbers ICMJE||H-24568|
|Has Data Monitoring Committee||No|
|Responsible Party||Joseph A. Vita, MD, Boston University|
|Study Sponsor ICMJE||Boston University|
|Collaborators ICMJE||Welch's, Inc.|
|Information Provided By||Boston University|
|Verification Date||June 2009|
ICMJE Data element required by the International Committee of Medical Journal Editors and the World Health Organization ICTRP