HOMOCYST

这个子项目是许多研究子项目中利用 资源由NIH/NCRR资助的中心拨款提供。子项目和 调查员(PI)可能从NIH的另一个来源获得了主要资金， 并因此可以在其他清晰的条目中表示。列出的机构是 该中心不一定是调查人员的机构。 阿尔茨海默病(AD)患者血中同型半胱氨酸水平升高，高同型半胱氨酸血症可能通过血管和直接神经毒性机制参与疾病的病理生理过程。大剂量补充叶酸和维生素B6和B12可以降低同型半胱氨酸水平。我们提出了一项多中心、随机、对照的临床试验，以确定大剂量叶酸/B6/B12补充剂降低同型半胱氨酸水平是否会减缓AD患者的认知衰退速度。这将是一项平行设计研究，包括两组不同大小的受试者：60%的受试者将接受每日高剂量补充剂(叶酸5毫克、维生素B6 25毫克、维生素B12 1毫克)，40%的受试者将接受相同的安慰剂；疗程为18个月。主要的结果衡量标准将是ADASCOG的纵向下降。为了支持试验以检测ADAScog下降降低25%(80%功率，阿尔法+0.05，辍学估计为20%，替代估计为10%)，我们将招募总共400名受试者。

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.