All studies reported outcomes using the Alzheimer’s Disease Assessment Scale-Cognitive Subscale (ADAS-Cog), scored 0 to 70, with lower numbers indicating better function, and the MMSE. Results of statin use were equivalent to placebo (ADAS-Cog MD= −0.26; 95% CI, −1.05 to 0.52; MMSE MD= −0.32; 95% CI, −0.71 to 0.06).
But do they slow its progression?
In contrast, a case-control study of 6431 patients with mild-to-moderate Alzheimer’s disease concluded that statin use was associated with slower progression of AD.6 Using cholinesterase inhibitor discontinuation as a proxy for worsening dementia, researchers noted that patients with early statin exposure (719 patients) had a lower rate of cholinesterase discontinuation than patients who didn’t receive early statin therapy (RR=0.85; 95% CI, 0.76-0.95).
A 2016 systematic review attempted to identify randomized clinical trials evaluating the effects of statin withdrawal in dementia.7 None were found.
RECOMMENDATIONS
Based primarily on post-marketing surveillance data, the US Food and Drug Administration (FDA) has warned that memory loss and confusion are occasionally associated with statin use from within one day to several years of initiation.8 The FDA indicated that such symptoms are rare, not associated with dementia or clinically significant cognitive decline, and resolve with discontinuation of the medication.