Association of statin use with risk of dementia: a meta-analysis of prospective cohort studies.

Statins are a class of medications that reduce cholesterol by inhibiting 3-hydroxy-3-methylglutaryl-coenzyme A reductase, which were thought to have a positive impact on dementia. We carried out the present meta-analysis to investigate whether statins might be associated with a reduction on risk of dementia. We carried out a meta-analysis of prospective cohort studies to examine the risk of dementia associated with statins. Ovid-Medline database, PubMed database, Springer Link database and Google Scholar in English search were carried out for relevant studies. Selected studies had to describe an original study defined by strict screening and diagnostic criteria. We included eight prospective cohort studies that reported relative risks with 95% confidence intervals for the association of statins and dementia risk. A random effects model was used to calculate the summary risk estimates. The studies eligible for analysis involved 2851 cases and 57020 participants. The summary relative risk of dementia for the use of statins was 0.62 (95% confidence interval 0.43-0.81), with evidence of heterogeneity (P = 0.001, I(2) = 70.8%). Findings of the present meta-analysis show that statin use was associated with a reduced risk of dementia.