ω-3 脂肪酸
一些动物研究调查了富含ω-3 脂肪酸的膳食鱼类或鱼油是否有助于预防 AD。对轻度至中度 AD 患者应用ω-3 脂肪酸不能延缓认知减退。[108]Burckhardt M, Herke M, Wustmann T, et al. Omega-3 fatty acids for the treatment of dementia. Cochrane Database Syst Rev. 2016;(4):CD009002.http://onlinelibrary.wiley.com/doi/10.1002/14651858.CD009002.pub3/fullhttp://www.ncbi.nlm.nih.gov/pubmed/27063583?tool=bestpractice.com [ 
]What are the effects of omega-3 fatty acids in people with Alzheimer's disease?http://cochraneclinicalanswers.com/doi/10.1002/cca.1423/full显示答案
他汀类药物
他汀类药物能降低循环胆固醇水平，并具有抗炎作用。这两种机制均可能减少 AD 患者的神经元损伤。将他汀类药物用于治疗和预防 AD 的可能性已经受到关注。然而，目前没有证据表明他汀类药物对 AD 有作用。[105]McGuinness B, Craig D, Bullock R, et al. Statins for the treatment of dementia. Cochrane Database Syst Rev. 2014;(7):CD007514.http://onlinelibrary.wiley.com/doi/10.1002/14651858.CD007514.pub3/fullhttp://www.ncbi.nlm.nih.gov/pubmed/25004278?tool=bestpractice.com[106]Feldman HH, Doody RS, Kivipelto M, et al. Randomized controlled trial of atorvastatin in mild to moderate Alzheimer disease: LEADe. Neurology. 2010;74:956-964.http://www.ncbi.nlm.nih.gov/pubmed/20200346?tool=bestpractice.com[107]Desilets AR. The role of statins in the prevention and treatment of Alzheimer's disease. J Pharm Technology. 2010;26:276-284.[150]Sparks DL, Connor DJ, Sabbagh MN, et al. Circulating cholesterol levels, apolipoprotein E genotype and dementia severity influence the benefit of atorvastatin treatment in Alzheimer's disease: results of the Alzheimer's Disease Cholesterol-Lowering treatment (ADCLT) trial. Acta Neurol Scand Suppl. 2006;185:3-7.http://www.ncbi.nlm.nih.gov/pubmed/16866904?tool=bestpractice.com[151]Zhou B, Teramukai S, Fukushima M. Prevention and treatment of dementia or Alzheimer's disease by statins: a meta-analysis. Dement Geriatr Cogn Disord. 2007;23:194-201.http://www.ncbi.nlm.nih.gov/pubmed/17259710?tool=bestpractice.com[152]Sun Y, Wang G, Pan Z, et al. Systematic review of atorvastatin for the treatment of Alzheimer's disease. Neural Regen Res. 2012;7:1344-1351.http://www.ncbi.nlm.nih.gov/pubmed/25657666?tool=bestpractice.com认知症状和功能：有低质量证据表明，他汀类药对痴呆或阿尔茨海默病风险无有益影响。[151]Zhou B, Teramukai S, Fukushima M. Prevention and treatment of dementia or Alzheimer's disease by statins: a meta-analysis. Dement Geriatr Cogn Disord. 2007;23:194-201.http://www.ncbi.nlm.nih.gov/pubmed/17259710?tool=bestpractice.com低质量的观察性（队列）研究或者受试者＜200名且方法学存在缺陷的随机对照临床试验（RCT）。 [ ]How do statins affect cognitive outcomes in people with normal cognitive function but risk factors for Alzheimer's or other cerebrovascular disease?http://cochraneclinicalanswers.com/doi/10.1002/cca.1232/full显示答案
Aβ1-42 疫苗接种
疫苗接种可减轻动物模型的Aβ斑负担，并改善其认知功能。一项在人类受试者中开展的免疫疗法研究，因治疗组有 6% 的脑膜脑炎发病率而被中断，但实际上接种活性疫苗的受试者中有不到 20% 达到了免疫应答目标水平。[153]Gilman S, Koller M, Black RS, et al. Clinical effects of Abeta immunization (AN1792) in patients with AD in an interrupted trial. Neurology. 2005;64:1553-1562.http://www.ncbi.nlm.nih.gov/pubmed/15883316?tool=bestpractice.com不幸的是，根据 ADAS-cog 和简易精神状态检查量表 (MMSE) 的评估结果，即使在产生应答的受试者中，也没有显著认知获益的证据。[153]Gilman S, Koller M, Black RS, et al. Clinical effects of Abeta immunization (AN1792) in patients with AD in an interrupted trial. Neurology. 2005;64:1553-1562.http://www.ncbi.nlm.nih.gov/pubmed/15883316?tool=bestpractice.comAD 的免疫疗法一直受到关注；在Ⅱ期试验中，不但有第二代抗原，还有采用预制的 Aβ 片段单克隆抗体或静脉内免疫球蛋白的被动免疫疗法。
分泌酶抑制剂
分泌酶抑制剂能抑制淀粉样蛋白前体蛋白分裂为有毒的淀粉样蛋白β片段。两种酶主要负责该片段：β和γ分泌酶。一项关于γ分泌酶抑制剂的试验，因为该药缺乏有效性，并且在较高剂量时，耐受性差，还可导致认知恶化，所以被停止。[154]Coric V, van Dyck CH, Salloway S, et al. Safety and tolerability of the gamma-secretase inhibitor avagacestat in a phase 2 study of mild to moderate Alzheimer disease. Arch Neurol. 2012;69:1430-1440.http://www.ncbi.nlm.nih.gov/pubmed/22892585?tool=bestpractice.comβ分泌酶调节剂仍在研发中。
