Vitamins Lower Homocysteine Levels, Not Stroke Risk 38672

Vitamins Lower Homocysteine Levels, Not Stroke Risk

WINSTON-SALEM, N.C.--High homocysteine levels have been linked withincreased risk of many types of cardiovascular diseases, including coronaryheart disease and high blood pressure. However, in a recent study, researchersfound high and low doses of folic acid, vitamin B6 and vitamin B12 lowerhomocysteine levels in subjects but did not reduce stroke risk. The study waspublished in the Feb. 4 issue of the Journal of the American MedicalAssociation (291, 5:565-75, 2004) (www.jama.ama-assn.org).

Approximately 3,600 adults who previously had a non-disabling stroke wereinvolved in the 6.5-year Vitamin Intervention for Stroke Prevention (VISP)randomized controlled trial. Subjects received a daily multivitamin with lowdoses of folic acid (20 mcg), vitamin B6 (200 mcg) and vitamin B12 (6 mcg), or adaily multivitamin with high doses of the same vitamins (2.5 mg, 25 mg and .4mg, respectively). Both the low- and high-dose multivitamins contained therecommended daily allowances of other vitamins.

Total homocysteine levels were lower in the high-dose group compared to thelow-dose group; however, this had no effect on treatment outcome. The chance ofhaving another stroke, a coronary heart disease event or succumbing to deathwithin two years after treatment was 18 percent in the high-dose group comparedto 18.6 percent in the low-dose group. In addition, the risk of ischemic strokewithin two years of treatment was 9.2 percent for the high-dose group comparedto 8.8 percent for the low-dose group. Researchers concluded the reducedhomocysteine levels in subjects had no effect on vascular outcome two yearsafter treatment; however, researchers did confirm the relationship betweenhomocysteine levels and vascular risk.

This trial was supported by the National Institute of Neurological Disordersand Stroke. The raw materials for the vitamins were supplied by Roche Vitamins,which was acquired in December 2003 by DSM Nutritional Ingredients, based inBasel, Switzerland.