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Vitamin C to Reduce Morning Cardiovascular Risk

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ClinicalTrials.gov Identifier: NCT03290612
Recruitment Status : Recruiting
First Posted : September 25, 2017
Last Update Posted : August 7, 2018
Sponsor:
Information provided by (Responsible Party):
Steven A. Shea, Oregon Health and Science University

Brief Summary:
This study will test the efficacy of Vitamin C to counteract morning CV risk markers in a randomized, double blind, placebo controlled crossover pilot study. The participants will also perform morning typical behaviors such as arousal from sleep, change in posture (getting out of bed) and mild intensity physical activity; identical to the stressors encountered in everyday life. Primary dependent variables are markers of cardiovascular risk including vascular endothelial function and oxidative stress.

Condition or disease Intervention/treatment Phase
Cardiovascular Risk Factor Dietary Supplement: Vitamin C Other: Placebo Not Applicable

Detailed Description:

The investigators plan to test the efficacy of Vitamin C to counteract morning CV risk markers in a randomized, double blind, placebo controlled crossover pilot study. The participants will also perform morning typical behaviors such as arousal from sleep, change in posture (getting out of bed) and mild intensity physical activity; identical to the stressors encountered in everyday life. This pilot study is in healthy middle aged adults without a history of CV disease.

Participants will spend two nights in an inpatient hospital suite at Hatfield Research Center. Upon awakening in the morning, they will either ingest Vitamin C or placebo in a randomized order. This will be followed by moderate intensity exercise, recovery, and discharge.


Study Type : Interventional  (Clinical Trial)
Estimated Enrollment : 20 participants
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
Masking Description: Vitamin C and Placebo doses will be blinded by the research pharmacy, so that participants and investigators are masked to the identity of the tablet. Data analysis will be blinded to the conditions as well until the completion of the study.
Primary Purpose: Supportive Care
Official Title: Chronotherapeutic Use of Vitamin C to Reduce Morning Cardiovascular Risk
Actual Study Start Date : February 13, 2018
Estimated Primary Completion Date : January 30, 2019
Estimated Study Completion Date : January 30, 2019

Resource links provided by the National Library of Medicine

MedlinePlus related topics: Vitamin C

Arm Intervention/treatment
Experimental: Vitamin C then Placebo
Participants will receive a 1.5g dose of Ascorbic Acid upon wake for the first visit, and a placebo tablet on the second visit.
Dietary Supplement: Vitamin C
1.5g Ascorbic Acid
Other Name: Ascorbic Acid

Other: Placebo
Inactive placebo to mimic 1.5g ascorbic acid.

Experimental: Placebo then Vitamin C
Participants will receive a placebo tablet upon wake for the first visit, and a 1.5g dose of Ascorbic Acid on the second visit.
Dietary Supplement: Vitamin C
1.5g Ascorbic Acid
Other Name: Ascorbic Acid

Other: Placebo
Inactive placebo to mimic 1.5g ascorbic acid.




Primary Outcome Measures :
  1. Vascular Endothelial Function [ Time Frame: Over two 2-day stays. ]
    Vascular endothelial function will be measured as FMD. We will measure FMD immediately upon awakening in a constant posture following an overnight fast using the standard guidelines and protocol.

  2. Oxidative stress [ Time Frame: Over two 2-day stays. ]
    We will quantify oxidative stress in plasma (i.e. ELISA for malondialdehyde (MDA) adduct).

  3. Plasma Vitamin C and Tetrahydrobiopterin [ Time Frame: Over two 2-day stays. ]
    We will measure Vitamin C levels in the plasma to ensure that the levels are increased after supplementation, and to control for baseline levels. We will measure BH4 from the plasma to test if levels are increased upon administration of Vitamin C.


Secondary Outcome Measures :
  1. Platelet aggregation [ Time Frame: Over two 2-day stays. ]
    Platelet aggregation will be measured using Chronolog 560 VS Platelet aggregometer.

  2. Plasminogen activator inhibitor -1 [ Time Frame: Over two 2-day stays. ]
    We will measure PAI-1 in the plasma



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Ages Eligible for Study:   40 Years to 60 Years   (Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes
Criteria

Inclusion Criteria:

  • Healthy participants
  • Normal weight or overweight but not obese (18.5<BMI<30 kg/m2)

Exclusion Criteria:

  • History of smoking/tobacco use
  • Current prescription/non-prescription medications or drugs of abuse
  • Acute, chronic, or debilitating medical conditions
  • History of working irregular day and night hours, regular night work, or rotating shift work for the six months prior to the study.

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 ClinicalTrials.gov identifier (NCT number): NCT03290612


Contacts
Contact: Saurabh S Thosar, PhD 5034942064 thosar@ohsu.edu
Contact: Leanna Williams, BS 5033463808 willeann@ohsu.edu

Locations
United States, Oregon
Oregon Health & Science University Recruiting
Portland, Oregon, United States, 97239
Contact: Saurabh S Thosar, PhD    503-494-2064    thosar@ohsu.edu   
Sponsors and Collaborators
Oregon Health and Science University

Responsible Party: Steven A. Shea, Director, Oregon Institute of Occupational Health Sciences, Oregon Health and Science University
ClinicalTrials.gov Identifier: NCT03290612     History of Changes
Other Study ID Numbers: IRB 00017294
First Posted: September 25, 2017    Key Record Dates
Last Update Posted: August 7, 2018
Last Verified: July 2018
Individual Participant Data (IPD) Sharing Statement:
Plan to Share IPD: Undecided

Studies a U.S. FDA-regulated Drug Product: No
Studies a U.S. FDA-regulated Device Product: No

Keywords provided by Steven A. Shea, Oregon Health and Science University:
Sleep
Vitamin C

Additional relevant MeSH terms:
Vitamins
Ascorbic Acid
Micronutrients
Growth Substances
Physiological Effects of Drugs
Antioxidants
Molecular Mechanisms of Pharmacological Action
Protective Agents