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Acute Effect of Nitrate From Natural Dietary Sources on Arterial Stiffness and Blood Pressures in Healthy Individuals (DNAB)

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. Identifier: NCT01604993
Recruitment Status : Completed
First Posted : May 24, 2012
Last Update Posted : March 10, 2014
Information provided by (Responsible Party):
St. Michael's Hospital, Toronto

Brief Summary:
The purpose of this study is to evaluate the acute effect of a meal high in dietary nitrates on aortic augmentation index, brachial and aortic blood pressures, and subendocardial viability ration (SEVR).

Condition or disease Intervention/treatment Phase
Healthy Other: Spinach soup Other: Asparagus soup Phase 2

Detailed Description:
Hypertension has become a common medical condition worldwide, raising public concern regarding the accompanying increase in cardiovascular disease risk and other health risks. Targets for optimal blood pressure are often unmet by conventional pharmaceutical therapies; consequently, complementary and alternative medicines are increasing in popularity among patients wishing to better manage their BP. In the case of hypertension, endothelial dysfunction and cardiovascular disease, a decline in the ability of blood vessels to dilate in response to shear stress is a major contributor to vascular pathology. At the core of these conditions is a decreased ability to synthesize nitric oxide, a potent vasodilatory agent. The proposed study will examine whether or not increasing the intake of dietary nitrate, which can be converted to nitric oxide endogenously, can improve three indices of vascular function that are validated risk factors for CVD: arterial stiffness, as measured by aortic augmentation index (AIx), aortic BP and brachial BP.

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Study Type : Interventional  (Clinical Trial)
Actual Enrollment : 31 participants
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Double (Participant, Investigator)
Primary Purpose: Health Services Research
Official Title: Acute Effect of Nitrate Supplementation From Natural Dietary Sources on Arterial Stiffness and Aortic and Brachial Blood Pressures: a Double-blind, Placebo-controlled, Randomized, Crossover Clinical Trial in Healthy Adults
Study Start Date : October 2011
Actual Primary Completion Date : November 2012
Actual Study Completion Date : October 2013

Arm Intervention/treatment
Experimental: High nitrate dietary source
556 grams of high nitrate spinach soup that is orally consumed as a single dose for 7 days.
Other: Spinach soup
556 g of high Nitrate spinach soup that is orally consumed as a single dose for 7 days

Placebo Comparator: No Nitrate dietary source
556g low nitrate asparagus soup; orally consumed as a single does for 7 days.
Other: Asparagus soup
556 grams of low nitrate asparagus soup that is orally consumed for a period of 7 days as a single does

Primary Outcome Measures :
  1. Aortic augmentation index (arterial stiffness) [ Time Frame: At each treatment visits, this measurement will be taken in at baseline, 1, 2, and 3 hours post-treatment. ]

Secondary Outcome Measures :
  1. Peripheral (brachial) and central (aortic) systolic and diastolic blood pressure [ Time Frame: Brachial blood pressure will be measured at 0 , 1, 2, and 3 hours post -treatmentbaseline and at 1, 2 and 3 hours at every visit. ]
  2. Subendocardial viability ratio (SEVR) [ Time Frame: At 1 hours intervals starting from baseline and ending at 3 hours. ]

Information from the National Library of Medicine

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Ages Eligible for Study:   18 Years to 50 Years   (Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes

Inclusion Criteria:

  • Healthy volunteers aged 18-50
  • Must consider themselves to be in good overall health and be free of any conditions or illnesses Women must be post-menopausal or not pregnant.
  • Body mass index (BMI) must be <30kg/m^2.
  • Normotensive, as defined by brachial SBP <140mmHg and DBP <90mmHg
  • Subjects must also be willing to stop using mouthwash for the duration of their participation in the study.

Exclusion Criteria:

  • Women of childbearing age may not be pregnant, planning to become pregnant, or breastfeeding at the time of the study
  • BMI >30kg/m^2
  • Hypertensive as defined by brachial SBP >140mmHg and/or DBP >90mmHg
  • Allergy or sensitivity to the study product, reference therapy or nitrates
  • Having any gastrointestinal complication or condition
  • Chronic use of medications such as prescription NSAIDs, antacids, blood-thinners, hypertensive medications, medications affecting NO synthesis such as Viagra, and use of antibiotics within one month of the study start
  • Individuals who are involved in another clinical trial.

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its identifier (NCT number): NCT01604993

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Canada, Ontario
Risk Factor Modification Centre
Toronto, Ontario, Canada, M5B 1W8
Sponsors and Collaborators
St. Michael's Hospital, Toronto
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Principal Investigator: Vladimir Vuksan, PhD Risk Factor Modification Centre - St. Michael's Hospital

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Responsible Party: St. Michael's Hospital, Toronto Identifier: NCT01604993     History of Changes
Other Study ID Numbers: 11216
First Posted: May 24, 2012    Key Record Dates
Last Update Posted: March 10, 2014
Last Verified: March 2014
Keywords provided by St. Michael's Hospital, Toronto:
Dietary Nitrates
Arterial Stiffness
Blood pressure