Statins, incident Alzheimer disease, change in cognitive function, and neuropathology.

OBJECTIVE: To examine the relation of statins to incident Alzheimer disease (AD) and change in cognition and neuropathology.
METHODS: Participants were 929 older Catholic clergy (68.7% women, mean baseline age 74.9 years, education 18.2 years, Mini-Mental State Examination 28.5) free of dementia, enrolled in the Religious Orders Study, a longitudinal clinical-pathologic study of AD. All agreed to brain autopsy at time of death and underwent annual structured clinical evaluations, allowing for classification of AD and assessment of cognition (based on 19 neuropsychological tests). Statins were identified by direct medication inspection. Neuropathologic data were available on 262 participants. All macroscopic chronic cerebral infarctions were recorded. A measure of global AD pathology was derived from silver stain, and separate measures of amyloid and tangles were based on immunohistochemistry. We examined the relation of statins to incident AD using Cox proportional hazards, change in cognition using mixed effects models, and pathologic indices using logistic and linear regression.
RESULTS: Statin use at baseline (12.8%) was not associated with incident AD (191 persons, up to 12 follow-up years), change in global cognition, or five separate cognitive domains (all p values > 0.20). Statin use any time prior to death (17.9%) was not related to global AD pathology. Persons taking statins were less likely to have amyloid (p = 0.02). However, among those with amyloid, there was no relation of statins to amyloid load. Statins were not related to tangles or infarction.
CONCLUSIONS: Overall, statins were not related to incident Alzheimer disease (AD) or change in cognition, or continuous measures of AD pathology or infarction.