Several studies have demonstrated the relationship between elevated homocysteine levels and coronary heart disease (CHD). A combination of folic acid, vitamin B6, and vitamin B12 is very effective in lowering homocysteine levels and was thought to have a protective effect against events associated with CHD. The results of a recent study, however, did not show a benefit in using this supplement to prevent recurrent events in patients with established CHD.
The Heart Outcomes Prevention Evaluation 2 study evaluated whether longterm administration of the combination reduces the risk of major vascular events (stroke, myocardial infarction [MI]) in a high-risk population. After an average follow-up of 5 years, plasma homocysteine levels were substantially reduced in the active group, versus placebo. There was no significant difference in the composite primary outcome (death from cardiovascular causes, MI, or stroke) or any of the secondary outcomes, however. There was a significant reduction in stroke, but the authors note that the number of strokes was much lower than the number of coronary events.
The outcomes were similar to those of other prospective studies in this area, and the authors concluded that the reduction in plasma homocysteine levels does not translate to a significant reduction in recurrent events in patients with established vascular disease. They also stated that more studies need to be done regarding atherothrombotic mediators, and alternative approaches to reducing homocysteine concentrations should be considered.
Dr. Garrett is a clinical pharmacist practitioner at Cornerstone Health Care in High Point, NC.