November 27, 2013
Large Review Shows No Negative Cognitive Effects
Philadelphia—With the release of new guidelines on controlling blood cholesterol to reduce cardiovascular risk in adults, more patients than ever could be prescribed statins. That makes a timely new report even more significant: Statins do not appear to cause memory loss or dementia in users.
Researchers from the University of Pennsylvania conducted the largest comprehensive systematic review to date and concluded that available evidence does not support an association between statins and memory loss or dementia. The results were published recently in the Annals of Internal Medicine.
“Statins are prescribed to approximately 30 million people in the United States,” said senior study author Emil deGoma, MD. “A wealth of data supports a benefit of these cholesterol-lowering medications among individuals at risk for cardiovascular disease in terms of a reduction in the risk of heart attack and stroke; however, potential side effects of statins are less well understood.”
Suggesting that a February 2012 FDA notice of possible adverse cognitive effects associated with statin use was “largely based on anecdotal reports,” deGoma added, “Many concerned patients have asked if there is a relationship between statins and memory problems. Their concerns, along with the FDA statement, prompted us to pursue a rigorous analysis of all available evidence to better answer the question—are statins associated with changes in cognition?”
With 57 of the studies reporting measures of cognitive function, the researchers found no evidence of an increased risk of dementia with statin therapy. To the contrary, according to the review, which points out that in cohort studies, statin users had a 13% lower risk of dementia, a 21% lower risk of Alzheimer’s disease, and a 34% lower risk of mild cognitive impairment compared to people who did not take statins.
In randomized controlled trials reviewed during the study, 55 cognitive tests measuring eight categories of cognitive function, including 26 tests of memory, revealed no differences between study participants treated with statins and those provided placebo.
Analysis of the FDA postmarketing surveillance databases by the researchers also found no difference in the frequency of cognitive adverse event reports between patients using statins and two commonly prescribed cardiovascular medications that have not been associated with cognitive impairment—clopidogrel and losartan.
“Overall, these findings are quite reassuring. I wouldn’t let concerns about adverse effects on cognition influence the decision to start a statin in patients suffering from atherosclerotic disease or at risk for cardiovascular disease,” deGoma advised. “I also wouldn't jump to the conclusion that statins are the culprit when an individual who is taking a statin describes forgetfulness. We may be doing more harm than good if we withhold or stop statins—medications proven to reduce the risk of heart attack and stroke—due to fears that statins might possibly cause memory loss.”
Researchers cautioned, however, that despite the reassuring results of their analysis, large, high-quality randomized controlled trials still are needed to confirm their findings.
“For many of the cognitive outcomes that we examined, the identified studies were small, were at risk for bias, used varying diagnostic tests to assess cognitive domains, and did not include patients on high-dose statins, which is important given the increasing use of high-dose statins for secondary prevention,” noted study coauthor Craig Umscheid, MD, MSCE.
The authors emphasize that the strength of available evidence is limited, especially relating to high-dose statins.
“Despite this,” Umscheid added, “the totality of the evidence does reassure us that there's unlikely to be a significant link between statins and cognitive impairment.”
|U.S. Pharmacist Social Connect