Effect of folic acid on endothelial function following acute myocardial infarction

Area of Science:

• Cardiovascular Medicine
• Endocrinology
• Nutritional Science

Background:

• Endothelial dysfunction is a key factor in cardiovascular disease progression after acute myocardial infarction (AMI).
• Homocysteine levels are implicated in endothelial dysfunction, and folic acid is known to reduce homocysteine.
• The specific impact of high-dose folic acid on endothelial function in post-AMI patients, independent of homocysteine levels, requires further investigation.

Purpose of the Study:

• To evaluate the effect of high-dose folic acid (10 mg/day) on endothelial function in patients post-AMI.
• To determine the relationship between folic acid supplementation, homocysteine levels, and endothelial function.
• To assess the impact on flow-mediated dilation (FMD) and nitroglycerin-mediated dilation.

Main Methods:

• A double-blind, randomized crossover trial involving 40 post-AMI patients.
• Patients received either high-dose folic acid (10 mg/day) or placebo for 6 weeks, followed by a 2-week washout period.
• Measurements included plasma folate, total homocysteine, FMD, and nitroglycerin-mediated dilation at baseline, 6 weeks, and 14 weeks.

Main Results:

• High-dose folic acid significantly improved FMD from 3.98% to 6.44% (p <0.001) in the active treatment group.
• The improvement in FMD persisted after crossover and was observed in both normo- and hyperhomocysteinemic patients.
• No significant changes were noted in nitroglycerin-mediated dilation, and FMD improvements did not correlate with homocysteine levels.

Conclusions:

• Six-week treatment with high-dose folic acid effectively improves endothelial function in post-AMI patients.
• The beneficial effect on endothelial function is independent of baseline homocysteine levels.
• High-dose folic acid supplementation is a potential therapeutic option for improving endothelial dysfunction in post-AMI patients with varying homocysteine statuses.