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

This study has been completed.
Information provided by (Responsible Party):
St. Michael's Hospital, Toronto Identifier:
First received: May 22, 2012
Last updated: March 7, 2014
Last verified: March 2014
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 Intervention Phase
Healthy Other: Spinach soup Other: Asparagus soup Phase 2

Study Type: Interventional
Study Design: Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Double Blind (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

Further study details as provided by St. Michael's Hospital, Toronto:

Primary Outcome Measures:
  • 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:
  • 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. ]
  • Subendocardial viability ratio (SEVR) [ Time Frame: At 1 hours intervals starting from baseline and ending at 3 hours. ]

Enrollment: 31
Study Start Date: October 2011
Study Completion Date: October 2013
Primary Completion Date: November 2012 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
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

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.

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.
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its identifier: NCT01604993

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

Responsible Party: St. Michael's Hospital, Toronto Identifier: NCT01604993     History of Changes
Other Study ID Numbers: 11216
Study First Received: May 22, 2012
Last Updated: March 7, 2014

Keywords provided by St. Michael's Hospital, Toronto:
Dietary Nitrates
Arterial Stiffness
Blood pressure processed this record on June 23, 2017