title: Efficacy and safety of cognitive enhancers for patients with mild cognitive impairment: a systematic review and meta-analysis.
abstract: BACKGROUND
  Cognitive enhancers, including cholinesterase inhibitors and memantine, are used to treat dementia, but their effectiveness for mild cognitive impairment is unclear. We conducted a systematic review to examine the efficacy and safety of cognitive enhancers for mild cognitive impairment.
  
  
  METHODS
  Our eligibility criteria were studies of the effects of donepezil, rivastigmine, galantamine or memantine on mild cognitive impairment reporting cognition, function, behaviour, global status, and mortality or harms. We identified relevant material by searching electronic databases (e.g., MEDLINE, Embase), the references of included studies, trial registries and conference proceedings, and by contacting experts. Two reviewers independently screened the results of the literature search, abstracted data and appraised risk of bias using the Cochrane risk-of-bias tool.
  
  
  RESULTS
  We screened 15,554 titles and abstracts and 1384 full-text articles. Eight randomized clinical trials and 3 companion reports met our inclusion criteria. We found no significant effects of cognitive enhancers on cognition (Mini-Mental State Examination: 3 randomized clinical trials [RCTs], mean difference [MD] 0.14, 95% confidence interval [CI] -0.22 to 0.50; Alzheimer's Disease Assessment Scale - cognition subscale: 3 RCTs, standardized MD -0.07, 95% CI-0.16 to 0.01]) or function (Alzheimer's Disease Cooperative Study activities of daily living inventory: 2 RCTs, MD 0.30, 95% CI -0.26 to 0.86). Cognitive enhancers were associated with higher risks of nausea, diarrhea and vomiting than placebo.
  
  
  CONCLUSIONS
  Cognitive enhancers did not improve cognition or function among patients with mild cognitive impairment and were associated with a greater risk of gastrointestinal harms. Our findings do not support the use of cognitive enhancers for mild cognitive impairment.
authors.forename: Andrea C
authors.initials: AC
authors.lastname: Tricco
authors.forename: Charlene
authors.initials: C
authors.lastname: Soobiah
authors.forename: Shirra
authors.initials: S
authors.lastname: Berliner
authors.forename: Joanne M
authors.initials: JM
authors.lastname: Ho
authors.forename: Carmen H
authors.initials: CH
authors.lastname: Ng
authors.forename: Huda M
authors.initials: HM
authors.lastname: Ashoor
authors.forename: Maggie H
authors.initials: MH
authors.lastname: Chen
authors.forename: Brenda
authors.initials: B
authors.lastname: Hemmelgarn
authors.forename: Sharon E
authors.initials: SE
authors.lastname: Straus
mesh_terms: D002800:Cholinesterase Inhibitors / Q000627:therapeutic use; D060825:Cognitive Dysfunction / Q000188:drug therapy*; D000077265:Donepezil; D005702:Galantamine / Q000627:therapeutic use; D006801:Humans; D007189:Indans / Q000627:therapeutic use; D008559:Memantine / Q000627:therapeutic use; D018697:Nootropic Agents / Q000627:therapeutic use*; D048448:Phenylcarbamates / Q000627:therapeutic use; D010880:Piperidines / Q000627:therapeutic use; D000068836:Rivastigmine; D016896:Treatment Outcome
chemical_list: D002800:Cholinesterase Inhibitors; D007189:Indans; D018697:Nootropic Agents; D048448:Phenylcarbamates; D010880:Piperidines; D005702:Galantamine; D000077265:Donepezil; D000068836:Rivastigmine; D008559:Memantine
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