Senior Psychcare

Lead author Dr. Emil deGoma, medical director of the Preventive Cardiovascular Program at the University of Pennsylvania in Philadelphia, called the data "reassuring."

"We found no evidence of an association involving statins and an elevated risk of dementia, a worsening of cognitive performance ratings, or an increased rate of cognitive-linked undesirable occurrence studies submitted to the FDA," Dr. deGoma reported in an email.

"For patients who are at risk for heart attack and stroke who are using statins to lessen that risk, I would not be concerned about statins causing memory impairment or dementia or various other forms of cognitive impairment."

The assessment, released online November 19 in Annals of Internal Medicine, included 57 studies, 25 of which were likewise included in a meta-analysis. In both cases, the majority of reports were cohort studies, with fewer randomized, controlled trials.

Surveying all of the research, the researchers observed no increased incidence of Alzheimer's disease, dementia or mild cognitive impairment and no difference in cognitive functionality, including procedural memory, attention, motor speed, global cognitive performance ratings, executive functionality, declarative memory, processing pace, or visuoperception among statin users.

However, they admit that the lack of well-powered randomized studies meant the evidence was either of low or modest quality.

The researchers additionally compared reviews of adverse cognitive incidents sent to the U. S. Food and Drug Administration for statins against accounts submitted for losartan and clopidogrel.

The proportion of reports to the FDA for cognitive problems were comparable amongst all three: 1. 3% for statins compared to 0. 7% for losartan and 0. 9% for clopidogrel.

Of all these, however, statins are the only substance with an FDA alert for cognitive impairment. On February 28, 2012, the FDA revised the prescribing label for statins to warn that memory loss and confusion have been reported with statin use.

Dr. Benjamin Wolozin of Boston University, a professor of pharmacology specializing in Alzheimer's and Parkinson's conditions, said the review was well done. He agreed with the authors' conclusions, but he said it's important to distinguish between the epidemiological perspective taken in the research and the legal one used by the FDA.

"You have to think about the way the FDA thinks," Dr. Wolozin said. "From an epidemiological perspective, there won't be any dissimilarities (in cognitive reduction); but I suspect that if you take specific subsets of people who have particular genetic predispositions, that statins could induce cognitive loss in those people, even in the same way it can lead to muscle pain, rhabdomyalgia, in certain sets of people who have certain genetic polymorphisms."