title: Use of statins and incidence of dementia and cognitive impairment without dementia in a cohort study.
abstract: OBJECTIVE
  Evidence of a relation between use of lipid lowering drugs and cognitive outcomes is mixed. This study aimed to test the association between use of statins and incidence of dementia and cognitive impairment without dementia (CIND) over 5 years of follow-up.
  
  
  METHODS
  Data were from a population-based cohort study comprising 1,789 older Mexican Americans. All participants had cognitive and clinical evaluations performed every 12 to 15 months. Participants who fell below specified cutpoints on cognitive tests were then evaluated clinically. Dementia diagnoses were finalized by an adjudication team. A total of 1,674 participants free of dementia/CIND at baseline were included in these analyses. Statin use was verified at each participant's home by medicine cabinet inspection. Cox proportional hazards models were used to evaluate the association between statin use and incidence of dementia/CIND.
  
  
  RESULTS
  Overall, 452 of 1,674 participants (27%) took statins at any time during the study. Over the 5-year follow-up period, 130 participants developed dementia/CIND. In Cox proportional hazards models adjusted for education, smoking status, presence of at least one APOE epsilon4 allele, and history of stroke or diabetes at baseline, persons who had used statins were about half as likely as those who did not use statins to develop dementia/CIND (HR = 0.52; 95% CI 0.34, 0.80).
  
  
  CONCLUSIONS
  Statin users were less likely to have incident dementia/cognitive impairment without dementia during a 5-year follow-up. These results add to the emerging evidence suggesting a protective effect of statin use on cognitive outcomes.
authors.affiliation: Department of Epidemiology, University of Michigan, Ann Arbor, MI, USA.
authors.forename: C
authors.initials: C
authors.lastname: Cramer
authors.forename: M N
authors.initials: MN
authors.lastname: Haan
authors.forename: S
authors.initials: S
authors.lastname: Galea
authors.forename: K M
authors.initials: KM
authors.lastname: Langa
authors.forename: J D
authors.initials: JD
authors.lastname: Kalbfleisch
mesh_terms: D000368:Aged; D001921:Brain / Q000187:drug effects* / Q000378:metabolism / Q000503:physiopathology; D003072:Cognition Disorders / Q000188:drug therapy* / Q000453:epidemiology / Q000517:prevention & control; D015331:Cohort Studies; D003704:Dementia / Q000188:drug therapy* / Q000453:epidemiology / Q000517:prevention & control; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors / Q000494:pharmacology* / Q000627:therapeutic use; D006937:Hypercholesterolemia / Q000150:complications / Q000188:drug therapy / Q000503:physiopathology; D015994:Incidence; D008297:Male; D008875:Middle Aged; D018696:Neuroprotective Agents / Q000494:pharmacology* / Q000627:therapeutic use; D016016:Proportional Hazards Models; D013995:Time; D016896:Treatment Outcome
chemical_list: D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors; D018696:Neuroprotective Agents