HOPE-2 Study (Heart Outcomes Prevention Evaluation-2 Study)

Cardiovascular disease (CVD) remains a major cause of mortality and morbidity in most developed countries and accounts for approximately 40% of all deaths in Canada. Reductions in cholesterol, lowering of blood pressure and smoking cessation have been shown to be effective strategies in cardiovascular prevention; however, these major "classical cardiovascular risk factors" along with nonmodifiable risk factors, cannot fully explain why certain individuals develop atherosclerotic cardiovascular diseases, while others do not. Other "emerging" cardiovascular risk factors are currently under investigation. There is a large body of consistent, biologically plausible evidence linking hyperhomocyst(e)inemia to cardiovascular risk and the association is graded. A simple, nontoxic therapeutic intervention in the form of multivitamins - folic acid and vitamins B6 and B12 - has been shown to be highly effective in reducing homocyst(e)ine levels, irrespective of the underlying cause. To date, however, there are no good clinical trials evaluating the efficacy of homocyst(e)ine-lowering therapies in reducing major cardiovascular events. The impact of this simple intervention on cardiovascular morbidity and mortality remains to be demonstrated. Study Hypothesis: Evaluate if long-term therapy with folic acid and vitamins B6 and B12 compared to placebo reduces the risk of major fatal and nonfatal cardiovascular events. Importance of the Study: The "homocyst(e)ine theory of atherosclerosis" remains an important unanswered question in cardiovascular medicine. If indeed a combination of multivitamins is found to be effective in reducing cardiovascular events, it is expected that this safe, inexpensive and easily administered therapy would be widely used world-wide. Therefore, the results of this trial could have a significant public health impact.