Dietary Nitrate and Physiological Aging

NCT02593305 | Completed Results

• 1 other identifier: 201507735
• Study Type: interventional
• Target: 23
• Locations: 1 country
• Sites: 1

Brief Summary

The main purpose/s of this study is to examine the effects of 4 weeks of dietary nitrate supplementation on peripheral chemoreceptor sensitivity, spontaneous baroreflex sensitivity, and blood pressure responsiveness to a variety of physiological stressors in older healthy adults. We will also examine the effect of dietary nitrate supplementation on measures of central artery stiffness and aortic blood pressure in older adults. Lastly, we will also recruit a group of young subjects in order to help characterize the age-related changes associated with the physiological outcome measures of the present study.

Conditions

Aging

Keywords

nitrate; blood flow; blood pressure; vascular function; hypoxia

Outcome Measures

Primary Outcomes (2)

• Change in Carotid Chemosensitivity Following 4 Weeks of Dietary Nitrate Supplementation and Placebo in Older Adults

  Carotid chemosensitivity examined by measuring hypoxia ventilatory responsiveness in older adults before and after 4 weeks of beet root juice supplementation and placebo. Chemoreflex sensitivity was quantified as the change in ventilation in relation to the change in pulse oxygen saturation.

  Pre and post 4 weeks dietary nitrate supplementation and pre and post 4 weeks of placebo.

• Change in Systolic Blood Pressure During Metaboreflex Testing Following 4 Weeks of Dietary Nitrate Supplementation and Placebo in Older Adults.

  Muscle metaboreflex examined by measuring systolic blood pressure responses to ischemic isometric muscle contraction in older adults before and after 4 weeks of beet root juice supplementation and placebo.

  Pre and post 4 weeks dietary nitrate supplementation and pre and post 4 weeks of placebo.

Study Arms (3)

Beetroot crystals (nitrate), then placebo

EXPERIMENTAL

Participants will receive a nitrate rich beetroot powder (10g/day) for 4 weeks. After a washout period of 4 weeks, they will then receive the placebo (beetroot powder, no nitrate) for 4 weeks.

Dietary Supplement: Super Beets; Dietary Supplement: Super Beets Placebo

Placebo, then beetroot crystals (nitrate)

EXPERIMENTAL

Participants will receive a beetroot powder placebo (no nitrate) for 4 weeks. After a 4 week washout period, they will receive the nitrate rich beetroot powder for 4 weeks.

Dietary Supplement: Super Beets; Dietary Supplement: Super Beets Placebo

Young Comparison

NO INTERVENTION

Young control group, used for age-related comparisons. This group did not go through any intervention.

Interventions

Super Beets DIETARY_SUPPLEMENT

Nitrate rich beetroot powder (10g/day) for 4 weeks

Also known as: Beetroot crystals

Beetroot crystals (nitrate), then placebo; Placebo, then beetroot crystals (nitrate)

Super Beets Placebo DIETARY_SUPPLEMENT

Nitrate deficient beetroot powder (10g/day) for 4 weeks

Also known as: Beetroot crystals no nitrate

Beetroot crystals (nitrate), then placebo; Placebo, then beetroot crystals (nitrate)

Eligibility Criteria

• Age: 18 Years - 85 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Healthy young adults 18-35 years of age (comparison group)
• Healthy older adults 60-85 years of age (intervention group)

You may not qualify if:

• Hypertension, hyperlipidemia, current smoker or smoker within the last year, heart disease, diabetes, Chronic obstructive pulmonary disease, asthma, sleep apnea, Raynaud's disease, body mass index (BMI) \> 30 kg/m2, allergy medication, clinical depression, autonomic disorders and other conditions or medications that might normally alter cardiovascular function, exercise tolerance, and/or blood pressure responses.

Sponsors & Collaborators

• Darren P Casey: lead
• Neogenis Laboratories: collaborator

Study Sites (1)

University of Iowa

Iowa City, Iowa, 52242, United States

Location

MeSH Terms

Conditions

Hypoxia

Condition Hierarchy (Ancestors)

Signs and Symptoms, Respiratory; Signs and Symptoms; Pathological Conditions, Signs and Symptoms

Limitations and Caveats

All subjects (young and older) completed the initial study visit. The young adults were used as a comparison group only and did not go through any intervention. The older adults underwent the intervention and completed a total of four study visits.

Results Point of Contact

• Title: Dr. Darren P. Casey
• Organization: University of Iowa

darren-casey@uiowa.edu

3193841009

Study Officials

• Darren Casey, PhD.

  University of Iowa

  PRINCIPAL INVESTIGATOR

Publication Agreements

• PI is Sponsor Employee: No
• Restrictive Agreement: No

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: DOUBLE
• Who Masked: PARTICIPANT, OUTCOMES ASSESSOR
• Purpose: BASIC SCIENCE
• Intervention Model: CROSSOVER
• Sponsor Type: OTHER
• Responsible Party: SPONSOR INVESTIGATOR
• PI Title: Assistant Professor

Study Record Dates

• First Submitted: October 27, 2015
• First Posted: November 2, 2015
• Study Start: October 1, 2015
• Primary Completion: April 28, 2017
• Study Completion: April 28, 2017
• Last Updated: October 14, 2019
• Results First Posted: October 14, 2019

Record last verified: 2019-09

Data Sharing

• IPD Sharing: Will not share

Locations

US (1)