Beetroot Juice Improves Fitness and Function in Patients With COPD

TOPLINE:

Daily consumption of beetroot juice significantly improved blood pressure, vascular function, and exercise capacity in adults with chronic obstructive pulmonary disease (COPD) over 12 weeks compared with a placebo drink.

METHODOLOGY: 

• Dietary nitrate has been associated with improved cardiovascular risk profiles, but the impact of nitrate supplementation in patients with COPD who have increased risk for cardiovascular disease has not been well studied.
• The researchers randomly assigned 81 adults with COPD and a systolic blood pressure (SBP) ≥ 130 mm Hg to nitrate-rich beetroot juice (NR-BRJ) — 70 mL of beetroot juice containing 400 mg of nitrate — or a placebo drink with no nitrate daily for 12 weeks.
• The primary outcome was a change in SBP based on home measurements; secondary outcomes were a change in 6-minute walking distance and changes in endothelial function based on the reactive hyperemia index (RHI) and augmentation index corrected for heart rate at 75 beats/min (AIx75).

TAKEAWAY:

• NR-BRJ consumption was significantly associated with decreased SBP compared with placebo, with a difference of -4.5 mmHg (P < .001).
• The NR-BRJ group also showed significant improvement compared with the placebo group in the secondary outcomes of 6-minute walking distance (average increase of 30 meters; P < .001) and endothelial function based on RHI (increase of 0.34; P = .03) and AIx75 (-7.61%; P = .026).
• Plasma nitric oxide (NOx) and fractional exhaled nitric oxide (FeNO) data were available for 24 patients in the NR-BRJ group and 20 in the placebo group; plasma NOx increased from baseline in the treatment group, but not the placebo group, and the increase in FeNO was significantly greater from baseline in the treatment group compared with the placebo group.
• No significant changes were noted between the groups in platelet aggregation and P-selectin expression.

IN PRACTICE:

"In this study, the substantial increases in plasma NOx concentration after NR-BRJ were associated with SBP reduction, providing further evidence that nitrate/nitrite reduction to NO most likely underlies the BP-lowering effects seen with BRJ consumption," the researchers wrote.

SOURCE:

The lead author on the study was Ali M. Alasmari, MD, of Imperial College, London. The findings were published online ahead of print in European Respiratory Journal in December 2023. 

LIMITATIONS:

The findings were limited by the relatively small sample size, the inability to conduct subgroup analyses, and the inclusion of only total NOx values.

DISCLOSURES:

The study was supported by a PhD scholarship from the Respiratory Department at Taibah University, Saudi Arabia. The researchers had no financial conflicts to disclose.