Coronary Artery Disease
Conditions
Brief summary
Older adults with coronary artery disease (CAD) have impaired vascular and inspiratory muscle function. The overarching goal of this double-blind, randomized, crossover, placebo-controlled pilot trial was to inform the development of a fully powered trial to evaluate the effects of dietary nitrate supplementation in older adults with CAD. We aimed to address the following objectives: (a) assess the feasibility, tolerability, and safety of the study protocol; (b) gather preliminary evidence on the effects of nitrate-rich beetroot juice compared with nitrate-depleted beetroot juice (placebo), and estimate the effect sizes; and (c) determine if a full-scale definitive trial is justified.
Interventions
DIETARY_SUPPLEMENTNitrate rich beetroot juice
Participants will drink nitrate rich beetroot juice (2.4 floz ; Beet It Sport Nitrate 400 concentrated beetroot shot; James White Drink, ltd) twice daily for two weeks.
DIETARY_SUPPLEMENTNitrate depleted beetroot juice
Participants will drink nitrate depleted beetroot juice (2.4 floz ; Beet It placebo concentrated beetroot shot; James White Drink, ltd) twice daily for two weeks.
Sponsors
University of Florida
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
BASIC_SCIENCE
Masking
TRIPLE (Subject, Investigator, Outcomes Assessor)
Eligibility
Sex/Gender
ALL
Age
60 Years to 85 Years
Healthy volunteers
No
Inclusion criteria
* Adults with coronary artery disease (CAD) based on an angiogram \>50% stenosis in any major epicardial vessel or history of myocardial infarction or history of coronary revascularization. * Considered to have stable CAD on optimal medical therapy * 60 to 85 years of age * Males and females (females must be postmenopausal either natural or surgical) * Able to give consent
Exclusion criteria
* Unstable angina, recent myocardial infarction or heart failure within 6 months * Coronary revascularization, including percutaneous coronary intervention and coronary artery bypass graft or thoracic surgery within 6 months. * Stroke, obstructive pulmonary disease, hepatitis B, C, HIV, seizures, or other relevant ongoing or recurrent illness * Individuals who have participated in respiratory training within the last 12 months or cardiac rehabilitation within the last 6 months * Uncontrolled hypertension * Use of tobacco products including smoking traditional or e-cigarettes * Use of hormone replacement therapy in women or men (e.g., estrogen, progesterone or testosterone) * Unwilling to stop using mouthwash at least 1 week before the start of the study and during study participation * Unwilling to remain weight stable during study participation
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Change in endothelial function | Baseline up to following 2 weeks of experimental condition | Endothelial function will be determined using brachial artery flow-mediated dilation via high resolution duplex ultrasonography. Reactive hyperemia will be produced by inflating a forearm cuff to \~250 mmHg for 5 minutes followed by rapid deflation. |
| Change in inspiratory muscle function | Baseline up to following 2 weeks of experimental condition | Inspiratory muscle function including strength, power and endurance will be assessed using the POWERbreathe KH2 device |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Change in microvascular function | Baseline up to following 2 weeks of experimental condition | Microvascular function will be assessed using the forearm blood flow response to submaximal handgrip exercise. Brachial artery blood flow and diameter will be assessed using ultrasound. |
| Change in central arterial stiffness | Baseline up to following 2 weeks of experimental condition | The SphygmoCor XCEL device will be used to measure carotid to femoral pulse wave velocity. |
| Change in central arterial hemodynamics | Baseline up to following 2 weeks of experimental condition | The SphygmoCor XCEL device will be used to obtain central pulse wave analysis. |
| Change in functional capacity | Baseline up to following 2 weeks of experimental condition | Using the Duke Activity Status Index we will assess participants' ability to perform daily activities. |
Countries
United States
Outcome results
None listed