LOWERING HOMOCYSTEINE LEVELS DOES NOT REDUCE RECURRENT VASCULAR EVENTS

Several studies havedemonstrated the relationshipbetween elevatedhomocysteine levelsand coronary heart disease(CHD). A combinationof folic acid, vitaminB₆, and vitamin B₁₂ is veryeffective in loweringhomocysteine levels and was thought tohave a protective effect against eventsassociated with CHD. The results of arecent study, however, did not show a benefitin using this supplement to preventrecurrent events in patients with establishedCHD.

The Heart Outcomes Prevention Evaluation2 study evaluated whether longtermadministration of the combinationreduces the risk of major vascular events(stroke, myocardial infarction [MI]) in ahigh-risk population. After an average follow-up of 5 years, plasma homocysteinelevels were substantially reduced in theactive group, versus placebo. There was nosignificant difference in the composite primaryoutcome (death from cardiovascularcauses, MI, or stroke) or any of the secondaryoutcomes, however. There was a significantreduction in stroke, but the authorsnote that the number of strokes was muchlower than the number of coronary events.

The outcomes were similar to those ofother prospective studies in this area, andthe authors concluded that the reductionin plasma homocysteine levels does nottranslate to a significant reduction in recurrentevents in patients with establishedvascular disease. They also stated thatmore studies need to be done regardingatherothrombotic mediators, and alternativeapproaches to reducing homocysteineconcentrations should be considered.

Dr. Garrett is a clinical pharmacistpractitioner at Cornerstone Health Carein High Point, NC.