B Vitamins Do Not Prevent Vascular Events After Stroke
B vitamin supplementation is safe but appears no more effective than placebo
WEDNESDAY, Aug. 4 (HealthDay News) -- Supplementation with folic acid, vitamin B6, and vitamin B12 is safe but does not appear to reduce the incidence of major vascular events in patients who have experienced a recent stroke or transient ischemic attack, according to a study published online Aug. 4 in The Lancet Neurology.
Graeme J. Hankey, M.D., of the Royal Perth Hospital in Australia, and colleagues randomized 8,164 patients with stroke or transient ischemic attack within the past seven months to receive one tablet daily of B vitamins (2 mg folic acid, 25 mg vitamin B6, and 0.5 mg vitamin B12) or placebo. The primary end point was the composite of stroke, myocardial infarction, or vascular death.
After a median follow-up of 3.4 years, the researchers found that 15 percent of patients assigned to B vitamin supplementation and 17 percent of those assigned to placebo reached the primary end point (risk ratio, 0.91; P = 0.05). In addition, the researchers found no significant differences in common adverse events among those who received B vitamin supplementation and those who received placebo, and there were no unexpected serious adverse events.
"Daily administration of folic acid, vitamin B6, and vitamin B12 to patients with recent stroke or transient ischemic attack was safe but did not seem to be more effective than placebo in reducing the incidence of major vascular events," the authors write. "These results do not support the use of B vitamins to prevent recurrent stroke."
Several authors disclosed financial ties to various pharmaceutical and medical device companies.