Screening and Management of Hyperhomocysteinemia for the Prevention of Coronary Artery Disease Events (2000)

There is insufficient evidence to include or exclude screening of tHcy levels in any population. Screening may enable identification of patients at high risk for CAD so that other risk factors can be managed aggressively. However, laboratory testing for homocysteine is currently restricted to research centres. Moreover, testing is not yet covered by provincial health insurance, and therefore patients may be required to cover the cost. (grade C recommendation)
Although folic acid effectively lowers plasma tHcy levels, there is insufficient evidence to suggest that its use would prevent CAD events. Adherence to the recommended daily allowance of dietary sources of folate and vitamins B6 and B12 may prevent hyperhomocysteinemia due to vitamin deficiency. Once elevated tHcy levels are discovered, vitamin deficiency should be ruled out to allow specific treatment and prevention of complications, such as neurological sequelae due to vitamin B12 deficiency. Some authorities recommend limiting folic acid intake to 1 mg/d or adding higher doses of vitamin B12 (0.2–1 mg/d) because of the theoretical risk of unmasking occult vitamin B12 deficiency. (grade C recommendation)