Objectives: To review available clinical trial data and discuss the potential role of statins on the development of Alzheimer's disease (AD).
Data sources: Searches of PubMed and MEDLINE (1985-February 2005) were conducted.
Study selection and data extraction: English language articles, review papers, and human studies with special emphasis on those dealing with statin use and AD.
Data synthesis: Early data from retrospective trials indicate that patients receiving statins have a reduced risk of developing AD. Two large published prospective clinical trials with cognition as secondary endpoint found that statins did not show any benefit compared with placebo. Only one of two more recent cohort community-based studies of statins found a lower risk of dementia and cognitive impairment. A small placebo-controlled pilot study reported that atorvastatin slows the progression of AD. Case reports indicate that in rare cases, statins may be associated with cognitive impairment. The results of ongoing placebo-controlled trials in patients with cognitive impairment should yield more definitive answers.
Conclusion: Current literature is conflicting with regard to the neuroprotective effects of statins on cognitive impairment. A firm conclusion regarding the effects of cholesterol or statins on human brain and cognitive function has not been well established, and it is premature to recommend statins for prevention and/or treatment of AD.