title: The role of lipid-lowering drugs in cognitive function: a meta-analysis of observational studies.
abstract: OBJECTIVE
  To quantify the risk of cognitive impairment with use of lipid-lowering drugs.
  
  
  METHODS
  Literature search through MEDLINE and EMBASE databases; data from seven observational studies were analyzed.
  
  
  RESULTS
  We quantified the risk of cognitive impairment first with the use of any lipid-lowering drug, and then specifically with the statins, using the random effects model. We tested for heterogeneity using the Q statistic as well as quantitatively using the Ri statistic. All seven studies provided data for statin users, and five provided data only on use of lipid-lowering drugs. Compared with patients not receiving lipid-lowering drugs, the relative risk of cognitive impairment with any lipid-lowering drug was 0.62 but was not statistically significant (95% confidence interval [CI] 0.28-1.38), and the relative risk with statins was 0.43 and was statistically significant (95% CI 0.31-0.62).
  
  
  CONCLUSIONS
  Lipid-lowering drugs--in particular, the statins--seem to lower the odds of developing cognitive impairment. Randomized, controlled trials are needed to address the efficacy of these agents specifically in different types of dementia.
authors.affiliation: Pharmacoepidemiology Unit, Royal Victoria Hospital, McGill University, Montreal, Quebec, Canada.
authors.forename: Mahyar
authors.initials: M
authors.lastname: Etminan
authors.forename: Sudeep
authors.initials: S
authors.lastname: Gill
authors.forename: Ali
authors.initials: A
authors.lastname: Samii
mesh_terms: D003071:Cognition / Q000187:drug effects*; D003072:Cognition Disorders / Q000139:chemically induced / Q000517:prevention & control*; D006801:Humans; D000960:Hypolipidemic Agents / Q000009:adverse effects / Q000494:pharmacology*; D012306:Risk
chemical_list: D000960:Hypolipidemic Agents