Does taking statins affect the pathological burden in autopsy-confirmed Alzheimer’s dementia?

BACKGROUND: The efficacy of cholesterol lowering agents, specifically statins, in slowing the rate of decline of cognitive function in Alzheimer’s disease (AD) patients is not yet fully understood. Our team’s previously published paper showed that patients who used statins demonstrated no increase in cognitive decline in mild cognitive impairment when compared with nonusers. Further, AD patients on statins demonstrated a slight decreasing trend in cognitive decline. The purpose of this study is therefore to investigate the association between stain use in AD confirmed by clinical diagnosis and autopsy and the pathological burden (plaques, tangles, Braak stage). The hypothesis leading this investigation is that prolonged statin use associates with lower AD pathology at autopsy. METHODS: We queried the National Alzheimer’s Coordinating Center (NACC) database for autopsy-confirmed AD cases. Of the Uniform Data Set (UDS) participants who are deceased, 16,163 were diagnosed with dementia at their last UDS visit prior to death, and autopsy data are available for 3945 patients. These patients were then stratified into two groups based upon statin use. The two groups were then analyzed for their pathological AD burden, including total plaques, total tangles, age at death, age of onset, and Braak stage. RESULTS: NACC data were available for 1816 subjects with clinically and pathologically confirmed AD; 1558 were not on statins and 258 were on statins. No significant differences in age at death, age at onset, Braak stages, mean total tau, and mean total amyloid were found between the two subject groups. When statin use was analyzed by apolipoprotein E (ApoE) genotype carrier statins, the presence of ApoE4 did not influence the effects (or lack thereof) of statin use. CONCLUSIONS: Prolonged statin use in pathologically confirmed AD dementia does not appear to influence the amount of burden of plaques and tangles or Braak stage. These observations were not altered by the presence of absence of ApoE4.