Pearls of Wisdom: Do Statins Cause Dementia?

Louis is a 68-year-old man in otherwise good health who several months ago received a recommendation for a statin for the primary prevention of cardiovascular disease. Today he has returned for a flu shot, and you note that he has not requested any refills for his statins. He has no known health problems and takes no other medications, including aspirin.

When you ask about his statin use, he reports that his aunt has dementia and that he has read several online sources mentioning that statins could cause dementia. Worried, he never filled the prescription.

Is there good evidence that statins cause dementia?

A. Yes
B. No
C. No, but they do cause mild cognitive impairment
D. No, but they worsen Alzheimer disease

What is the correct answer?
(Answer and discussion on next page)

Louis Kuritzky, MD, has been involved in medical education since the 1970s. Drawing upon years of clinical experience, he has crafted each year for almost 3 decades a collection of items that are often underappreciated by clinicians, yet important for patients. These “Pearls of Wisdom” often highlight studies that may not have gotten traction within the clinical community and/or may have been overlooked since their time of publishing, but warrant a second look.

Answer: No, statins do not cause dementia.

In response to isolated case reports, the FDA has been investigating the potential relationship between statins and cognition for several years. Clinicians should remember that simply having an association does not prove causation, and they should be vigilant about their patient’s interpretation of statements such as “there is an association between X and Y.”

A 2013 report reminds clinicians that in the face of unsubstantiated claims of cognitive dysfunction related to statins, patients who need the drugs for cardiovascular benefits should not stop taking them.

Statins and Cognition: Meta-Analysis

A meta-analysis by Richardson et al¹—a compilation of data from 3 randomized controlled trials, 16 cohort studies, 4 case-control studies, and 4 cross-sectional studies, totaling more than 4 million individuals—found 3 important findings:

• There is no association between all-cause dementia and statins.
• There is no association between Alzheimer disease dementia and statins.
• There is no association between mild cognitive impairment and statins.

The researchers summarized by saying that “published data do not suggest an adverse effect of statins on cognition; however, the strength of available evidence is limited, particularly with regard to high-dose statins.”¹

Statins and Dementia: NOT

Note: The meta-analysis actually detected a 13% lesser risk of all-cause dementia, a 21% lesser risk of Alzheimer disease, and a 34% lesser risk for mild cognitive impairment among users of statins than non-users.

If you and your patient still believe that there is a cardiovascular risk reduction advantage to statins, the patient should be reassured that there is no demonstrable risk of statins worsening the likelihood of dementia onset.

What’s the “Take Home”?

There have been dozens of false alarms reported relating to highly efficacious pharmacotherapies in the past decade. It is wise to be vigilant about adverse event case reports; however, keep in mind that to deprive a patient of a medication that could be life-saving or serious event-reducing should only be motivated by convincing evidence of the alleged adverse effect. And, remember: Despite the potential for favorable effects, every medication can be associated with some significant adverse effect for some patients.

Reference:

1. Richardson K, Schoen M, French B, et al. Statins and cognitive function: a systematic review. Ann Intern Med. 2013;159(10):688-697.