Working...
ClinicalTrials.gov
ClinicalTrials.gov Menu

Effect of Beetroot Juice on Coronary Blood Flow and Walking Performance in PAD (HeartBeet)

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. Know the risks and potential benefits of clinical studies and talk to your health care provider before participating. Read our disclaimer for details.
ClinicalTrials.gov Identifier: NCT02553733
Recruitment Status : Recruiting
First Posted : September 18, 2015
Last Update Posted : January 7, 2019
Sponsor:
Collaborators:
Milton S. Hershey Medical Center
Wake Forest University Health Sciences
Information provided by (Responsible Party):
David N. Proctor, PhD, Penn State University

Brief Summary:
In this study the investigators will test the hypothesis that short-term consumption of inorganic nitrate (supplied in concentrated beetroot juice) enhances coronary blood flow responses, large artery hemodynamics, and leg oxygenation/exercise tolerance in patients with peripheral arterial disease (PAD). Understanding and improving blood flow regulation in the heart and skeletal muscles of patients with PAD is important because exercise triggers symptoms of leg pain and substantially raises blood pressure and myocardial demand in these patients.

Condition or disease Intervention/treatment Phase
Peripheral Arterial Disease Drug: Beetroot juice Drug: Beetroot juice placebo Phase 2

Detailed Description:

Peripheral arterial disease (PAD) is a strong predictor of cardiovascular mortality and negatively affects functional capacity and quality of life for as many as 14 million patients in the U.S. alone. One open-label study showed that acute consumption of beetroot juice improved 6 min walk performance, reduced blood pressure, and enhanced leg muscle oxygenation in PAD patients. However, no studies have rigorously confirmed these findings in a double-blind manner, nor have the effects of this supplement been investigated (acutely or short-term) in the coronary circulation of PAD patients.

In addition to studying its effects on graded treadmill walking performance and consequent large artery vasodilation, the present study will examine the effects of short-term beetroot juice consumption (twice/day) on both coronary and leg vasodilator (graded calf flexion) and vasoconstrictor (isometric handgrip, voluntary apnea) responses in patients with PAD. Participants will randomly consume either nitrate-rich or nitrate-depleted beetroot juice with a 7 to 14 day wash-out period between. Effects of beetroot juice consumption on plasma nitrate, nitrite and methemoglobin will also be assessed.


Layout table for study information
Study Type : Interventional  (Clinical Trial)
Estimated Enrollment : 12 participants
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Double (Participant, Investigator)
Primary Purpose: Treatment
Official Title: Effects of Dietary Nitrate Supplementation on Coronary Blood Flow and Walking Performance in Peripheral Arterial Disease
Study Start Date : December 2015
Estimated Primary Completion Date : December 2020
Estimated Study Completion Date : December 2022

Resource links provided by the National Library of Medicine


Arm Intervention/treatment
Active Comparator: Beetroot juice (Beet-It Organic Shot)
Subjects will consume 70 ml of beetroot juice (Beet-It Organic Shot) twice per day (morning, afternoon) for 5 to 7 days to assess the short term effects of this nitrate supplement on graded treadmill walking responses (day 4) and vasodilator/vasoconstrictor responses in the coronary and lower leg circulations (day 5 or 6 or 7). On both study visits, subjects will consume their morning dose 1 hour 45 min before experiments begin.
Drug: Beetroot juice
This beverage contains 0.3 g of inorganic nitrate per 70 ml container, and is bottled and supplied by James White Drinks (UK).
Other Name: Beet-It Organic Shot

Placebo Comparator: Beetroot juice placebo (Beet-It Organic Placebo)
Subjects will consume 70 ml of beetroot juice placebo (Beet-It Organic Placebo) twice per day (morning, afternoon) for 5 to 7 days to assess the short term effects of this nitrate supplement on graded treadmill walking responses (day 4) and vasodilator/vasoconstrictor responses in the coronary and lower leg circulations (day 5 or 6 or 7). On both study visits, subjects will consume their morning dose 1 hour 45 min before experiments begin.
Drug: Beetroot juice placebo
This beverage is identical in look and taste to the Beet-It organic shot, but has the nitrate removed. It is also bottled and supplied by James White Drinks (UK).
Other Name: Beet-It organic placebo




Primary Outcome Measures :
  1. Exercise performance [ Time Frame: 5 to 7 days after initiating daily ingestion of beetroot juice ]
    Exercise capacity will be assessed using a graded treadmill walking test to peak exertion with expired gas analysis and determination of peak oxygen uptake, calf muscle oxygenation, blood pressure, claudication onset time, and peak walking time.


Secondary Outcome Measures :
  1. Coronary vascular function [ Time Frame: 4 days after initiating daily ingestion of beetroot juice ]
    Coronary artery (transthoracic ultrasound) blood flow responses to plantar flexion and handgrip exercise.

  2. Leg vascular function [ Time Frame: 4 days after initiating daily ingestion of beetroot juice ]
    Popliteal artery and near infrared spectroscopy (NIRS) responses to plantar flexion and handgrip exercise.


Other Outcome Measures:
  1. Blood measures of nitrate absorption and conversion [ Time Frame: 4 to 7 days after initiating ingestion of beetroot juice ]
    Venous blood will be withdrawn (venipuncture) for determination of plasma nitrate, nitrite and methemoglobin levels



Information from the National Library of Medicine

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, Learn About Clinical Studies.


Layout table for eligibility information
Ages Eligible for Study:   21 Years to 85 Years   (Adult, Older Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No
Criteria

Inclusion Criteria:

  1. Patients with peripheral arterial disease (PAD)
  2. Capable of giving informed consent
  3. Men and women age 21- 85 years
  4. Diagnosed with PAD (i.e., ankle-brachial index below 0.9)
  5. Fontaine stage II or less - no pain while resting
  6. Satisfactory history and physical exam

Exclusion Criteria:

  1. Children
  2. Pregnant or nursing women
  3. Patients taking nitroglycerine or nitrate preparations
  4. Patients taking phosphodiesterase inhibitors such as sildenafil or tadalafil
  5. Patients taking proton pump inhibitors
  6. Ejection fraction < 40%
  7. Uncontrolled hypertension
  8. Uncontrolled diabetes
  9. Myocardial infarction within past 6 months or unstable angina
  10. Severe lung disease (i.e., on supplemental oxygen or frequently use rescue inhalers)
  11. Abnormality in hemoglobin or hematocrit or methemoglobin
  12. Impaired renal function
  13. Impaired liver function
  14. History or diagnosis of Barrett's esophagus
  15. Known allergy to beetroot juice or lemon juice
  16. Inability to walk on a treadmill at a moderate pace (2.0 miles/hour)

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): NCT02553733


Contacts
Layout table for location contacts
Contact: David N Proctor, PhD 814-863-0724 dnp3@psu.edu

Locations
Layout table for location information
United States, Pennsylvania
Milton S. Hershey Medical Center Recruiting
Hershey, Pennsylvania, United States, 17033
Contact: Urs A Leuenberger, MD    717-531-7455    uleuenberger@hmc.psu.edu   
Sponsors and Collaborators
David N. Proctor, PhD
Milton S. Hershey Medical Center
Wake Forest University Health Sciences
Investigators
Layout table for investigator information
Principal Investigator: Urs A Leuenberger, MD Penn State University

Layout table for additonal information
Responsible Party: David N. Proctor, PhD, Professor of Kinesiology and Physiology, Penn State University
ClinicalTrials.gov Identifier: NCT02553733     History of Changes
Other Study ID Numbers: 00003242
First Posted: September 18, 2015    Key Record Dates
Last Update Posted: January 7, 2019
Last Verified: January 2019

Layout table for additional information
Studies a U.S. FDA-regulated Drug Product: Yes
Studies a U.S. FDA-regulated Device Product: No

Keywords provided by David N. Proctor, PhD, Penn State University:
Dietary nitrate supplementation
Beetroot juice

Additional relevant MeSH terms:
Layout table for MeSH terms
Peripheral Arterial Disease
Peripheral Vascular Diseases
Atherosclerosis
Arteriosclerosis
Arterial Occlusive Diseases
Vascular Diseases
Cardiovascular Diseases