Tools for Practice Outils pour la pratique

#115 Statins and cognitive impairment: Don’t forget the evidence?

Do statins have any effect on cognitive function or dementia?

Available evidence indicates that statins do not prevent, treat, or cause cognitive impairment or dementia. The FDA warning seems to be based primarily on case reports that may reflect idiosyncratic short-term “fuzzy” thinking. Decisions to prescribe statins should not be altered.  

CFPCLearn Logo

Reading Tools for Practice Article can earn you MainPro+ Credits

La lecture d'articles d'outils de pratique peut vous permettre de gagner des crédits MainPro+

Join Now S’inscrire maintenant

Already a CFPCLearn Member? Log in

Déjà abonné à CMFCApprendre? Ouvrir une session

Five systematic reviews:1-5  
  • Overall [57 studies (19 Randomized Controlled Trials (RCT), 26 cohort, six case-control, six cross-sectional)]:1  
    • Incidence of dementia or cognitive impairment:  
      • One RCT (20,536 patients): no effect.  
      • Observational studies: generally statins reduce the incidence.  
        • Example: ten cohort studies (4,360,137 patients), Relative Risk 0.87 [0.82-0.92].  
        • These results are less reliable due to biases like lower risk people more likely to use statins. 
    • Performance on cognitive function testing:  
      • Eighteen RCTs (8,305 patients) including healthy, high cholesterol, or demented patients using a variety of cognitive tests: 
        • Of 155 statistical comparisons, 87.7% no effect, 4.5% statin better, 7.7% placebo better. 
        • Largest (5,804 patients), mean age 75, non-demented, followed three years: no difference in mini mental state examination (MMSE). 
    • Post-marketing surveillance on cognitive adverse events: 
      • No difference between statins and clopidogrel or losartan.   
  • Statins preventing dementia [two RCTs (26,340 patients)]:2 
    • No effect 
    • Limits: cognitive function secondary outcome.  
  • Statins treating dementia [three RCTs (748 patients, mean age 79, with probable or possible Alzheimer’s disease, followed ≥6 months)]:3  
    • No effect. 
    • Trends generally favour statins preventing cognitive decline.  
      • Example: MMSE scores between statin and placebo (mean difference  -1.53, (-3.28 to 0.21). Not statistically significant. 
      • Limitations: highly inconsistent results. 
  • Two other systematic reviews found similar.4,5  
  • In 2012, the U.S. FDA warned that statins may produce cognitive impairment and memory loss/forgetfulness/confusion.6  
    • Appears based primarily on case reports.1  
    • May be better described as a “fuzzy” or unfocused thinking reaction.6 
      • It appears this is idiosyncratic, rare, and resolves when the medicine is stopped.6-8  
  • It has been proposed that lipophilic statins are more likely to cross blood-brain barrier and may have more central nervous system effects.6,7  
    • This is not based on reliable clinical evidence.  

Latest Tools for Practice
Derniers outils pour la pratique

#367 Oral Calcitonin Gene-related Peptide Antagonists: A painfully long name for the acute treatment of migraines

What are the risks and benefits of ubrogepant for the acute treatment of episodic migraines?
Read Lire 0.25 credits available Crédits disponibles

#366 Looking for Closure: Managing simple excisions or wounds efficiently

What are some options for efficiency in wound closure?
Read Lire 0.25 credits available Crédits disponibles

#365 Shrooms for Glooms: Evidence for psilocybin for depression

What are the benefits and harms of psilocybin for treatment-resistant/recurrent depression?
Read Lire 0.25 credits available Crédits disponibles

This content is certified for MainPro+ Credits, log in to access

Ce contenu est certifié pour les crédits MainPro+, Ouvrir une session

  • G. Michael Allan MD CCFP
  • Grenvil Gracias MSc MD

1. Richardson K, Schoen M, French B, et al. Ann Intern Med. 2013; 159:688-97.

2. McGuinness B, Craig D, Bullock R, et al. Cochrane Database Syst Rev. 2009; (2):CD003160.

3. McGuinness B, Craig D, Bullock R, et al. Cochrane Database Syst Rev. 2010; (8):CD007514.

4. Swiger KJ, Manalac RJ, Blumenthal RS, et al. Mayo Clin Proc. 2013; 88(11):1213-21.

5. Macedo AF, Taylor FC, Casas JP, et al. BMC Med. 2014; 12:51.

6. U.S. Department of Health and Human Services: Food and Drug Administration (FDA). FDA Drug Safety Communication: Important safety label changes to cholesterol-lowering statin drugs; 2012. Available from: (Accessed May 6, 2014)

7. Kelley BJ, Glasser S. CNS Drugs. 2014; 28(5):411-9.

8. Rojas-Fernandez CH, Cameron JC. Ann Pharmacother. 2012; 46(4):549-57.

Authors have no conflicts to disclose.