Should patients with coronary disease and high homocysteine take folic acid?

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Q&A

Should patients with coronary disease and high homocysteine take folic acid?

J Fam Pract. 2003 January;52(1):12-31

By

John J. O’Connor, MD

Linda N. Meurer, MD, MPH

BACKGROUND: Should patients with coronary artery disease and high homocysteine levels take folic acid? Plasma homocysteine levels predict outcome after coronary angioplasty, and lowering plasma homocysteine levels significantly decreases restenosis after coronary angioplasty.
STUDY POPULATION: The investigators enrolled 553 participants who had successfully undergone angioplasty for at least one significant coronary stenosis (≥50%). Subjects in the treatment and control groups were predominantly male (79% and 82%), and had mean ages of 62 and 63 years. Patients were excluded if they had unstable angina, subacute myocardial infarction (within the previous 2 weeks), renal insufficiency (serum creatinine >1.8 mg/dL), or were taking vitamins.
STUDY DESIGN AND VALIDITY: The study was a randomized, double-blind, placebo-controlled trial. After successful angioplasty, defined as residual diameter stenosis less than 35% with normal flow pattern (TIMI III criteria), patients were randomly assigned to receive a supplement containing folic acid (1 mg), vitamin B₁₂ (400 μg), and vitamin B₆ (10 mg) or placebo daily for 6 months. Treatment was discontinued after 6 months and the participants were then followed for another 6 months. Fasting total plasma homocysteine levels were measured on admission and at 6 months.
OUTCOMES MEASURED: The main outcomes evaluated were death, cardiac death (defined as sudden, unexpected death or death related to myocardial infarction), nonfatal myocardial infarction (new Q-wave in 2 or more electrocardiogram leads), the need for repeat revascularization for proven ischemia demonstrated by either follow-up cardiac events or a positive noninvasive stress test with significant angiographic stenosis of at least 50%, or a composite of these outcomes.
RESULTS: The composite outcomes of death, cardiac death, recurrence, or need for revascularization was significantly decreased with the vitamin therapy (hazard ratio, 0.68; 95% confidence interval [CI], 0.48–0.96). For the 6 months after the angioplasty, one outcome would have been avoided for every 13 patients treated. Individually, only the need for repeat revascularization was significantly affected by therapy (hazard ratio, 0.62; 95% CI, 0.40–0.97). Adjustment for multiple risk factors including age, sex, and variables known to influence the need for target lesion revascularization after coronary angioplasty (use of stents, treatment of restenotic lesions, vessel size, post procedural minimal luminal diameter, target lesion location, and use of glycoprotein IIb/IIIa inhibitors) did not significantly change the relationship between homocysteine-lowering therapy and the need for repeat target lesion revascularization.

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Should patients with coronary disease and high homocysteine take folic acid?

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