Effect of Beet Juice Supplementation on Vascular and Inspiratory Muscle Function

Effect of Beet Juice Supplementation on Vascular and Inspiratory Muscle Function

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.

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