A systematic review of available evidence uncovered no association between the use of statins and adverse cognitive outcomes, despite an FDA warning regarding such a relationship.
On February 28, 2012, the FDA announced safety changes to the labeling of statins to warn users that memory loss and confusion had been reported in connection with these agents. The FDA affirmed that these events generally were not serious and disappeared with the discontinuation of statin use. The agency also stated on July 3, 2012, that it continued to believe the cardiovascular benefits of statin therapy outweighed the small increase in cognitive risks.
Noting that despite the FDA warning, the relationship between statins and cognition remained unknown, Karl Richardson, MD, and colleagues undertook an analysis of randomized controlled trials as well as cohort, case-control, and cross-sectional studies evaluating cognition in patients receiving statins.
Low-quality evidence suggested no increased incidence of Alzheimer disease for statin users and no difference in cognitive performance related to procedural memory, attention or motor speed.
Moderate-quality evidence suggested no increased incidence of dementia or mild cognitive impairment, or any change in cognitive performance related to global cognitive performance scores, executive function, declarative memory, processing speed, or visuoperception.
Interestingly, in cohort studies, the risk for dementia was 13% lower among statin users than among nonusers; the risk for Alzheimer disease was 21% lower for statin users; and the risk for mild cognitive impairment was 34% lower for statin users.
Data showed that the reporting rate for cognitive-related adverse events with statins was low and was similar to the rates seen with other commonly prescribed cardiovascular medications.