HOMOCYST

这个子项目是众多研究子项目之一

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Blood levels of Homocysteine are elevated in Alzheimer's disease (AD), and hyperhomocyteinemia may contribute to disease pathophysiology by vasculare and direct neurotoxic mechanisms. Homocyteine levels can be reduced by administration of high dose supplements of folic acid and vitamins B6 and B12. We propose a multicenter, randomized, controlled clinical trial to determine whether reduction of homocysteine levels with high dose folic acid/B6/B12 supplementation will slow the rate of cognitive decline in subjects with AD. This will be parallel design study, including two groups of unequal size: 60% of subjects will receive daily high-dose supplements (folic acid 5mg, vitamin B6 25mg, vitamin B12 1mg), and 40% will receive identical placebo; the duration of treatment will be 18 months. The primary outcome measure will be the longitudinal decline in the ADAScog. To power the trial to detect a 25% reduction of ADAScog decline (80% power, alpha+0.05, drop-out estimate 20%, drop-in estimate 10%), we will enroll a total of 400 subjects.