BOSTON, MASSACHUSETTS. A high blood level of the amino acid homocysteine has been implicated as a risk factor for heart disease. A group of American researchers now provide convincing proof that a high homocysteine level is also a potent risk factor for stroke. Their investigation involved 1947 participants in the Framingham Study (1158 women and 789 men with a mean age of 70 years) who had their homocysteine levels (non-fasting) measured between May 1979 and May 1982 and were subsequently followed-up through to May 1992. By the end of the study 165 strokes had occurred among this group of elderly people. A high homocysteine level (greater than 14.24 micromol/L) was found to be associated with a 153 per cent increase in the risk of stroke when compared to the incidence among participants having a level of 9.25 micromol/L or less. The stroke risk increased linearly with increasing homocysteine level. The increased risk associated with a high homocysteine level was reduced to 82 per cent (from 153 per cent) after adjusting for other variables known to affect stroke risk such as age, high systolic blood pressure, smoking, diabetes, heart disease, and atrial fibrillation. (Editor's note: Homocysteine levels can be safely reduced by supplementing with folic acid, vitamin B6 and vitamin B12).
Bostom, Andrew G., et al. Nonfasting plasma total homocysteine levels and stroke incidence in elderly persons. Annals of Internal Medicine, Vol. 131, September 7, 1999, pp. 352-55