title: How useful are cholinesterase inhibitors in the treatment of Alzheimer's disease? A number needed to treat analysis.
abstract: OBJECTIVE
  To report on a Numbers Needed to Treat (NNT) analysis of the literature identified through a systematic review of trials of cholinesterase inhibitors in Alzheimer's Disease.
  
  
  METHODS
  Search of Medline (1966-1998), EMBASE (1994-1999) and Psychlit (1974-1998) using the keywords cholinesterase and placebo dementia.
  
  
  METHODS
  Double-blind, randomised, placebo-controlled trials.
  
  
  METHODS
  People with Alzheimer's Disease.
  
  
  METHODS
  Drug trials of acetylcholinesterase inhibitors (ChIs). Main outcome measuresAlzheimer's Disease Assessment Scale (Cognitive subscale), Clinician's Interview Based Impression of Change Plus, Mini Mental State Examination, Progressive Deterioration Scale.
  
  
  RESULTS
  Small numbers of patients (in most cases between 3 and 7) need to be treated with appropriate dosages of ChIs to ameliorate the clinical symptoms, or postpone deterioration in one of them.
  
  
  CONCLUSIONS
  These small NNTs suggest that, despite their expense, the cholinesterase inhibitors have a valuable place in the current clinical management of AD.
authors.affiliation: Department of Psychiatry and Behavioural Sciences, Royal Free and University College Medical School, Wolfson Building, London, UK. g.livingston@ucl.ac.uk
authors.forename: G
authors.initials: G
authors.lastname: Livingston
authors.forename: C
authors.initials: C
authors.lastname: Katona
mesh_terms: D000544:Alzheimer Disease / Q000188:drug therapy*; D002800:Cholinesterase Inhibitors / Q000627:therapeutic use*; D006801:Humans; D016032:Randomized Controlled Trials as Topic / Q000706:statistics & numerical data
chemical_list: D002800:Cholinesterase Inhibitors