Contradicting earlier research, a new study of nearly one million patients found that cholesterol-lowering statin drugs most likely do not cause short-term memory loss.

The Rutgers University and University of Pennsylvania study compared new users of statins with those not taking statins. New statin users also were compared to patients taking nonstatin LLDs in a second control group, in a comparison which had not been made before.

Lead author Brian L. Strom, chancellor of Rutgers Biomedical and Health Sciences (RBHS), said that previous small scale studies as well as some statin-drug takers have anecdotally reported memory lapses after taking popular lipid-lowering drugs (LLDs) called statins. Some people have inappropriately ceased taking their statins as a result, Strom said.

More patients taking statins did actually report memory loss in the 30-day period after first taking the drugs, compared to non-users, the study found.

But the same patter was seen with the nonstatin LLDs.

Detection Bias?

“Either it means that anything that lowers cholesterol has the same effect on short-term memory, which is not scientifically credible because you’re dealing with drugs with completely different structures,” Strom said.

“Detection bias”, he said, is more likely the reason. This is when patients taking a new drug visit their doctors more frequently and are more tuned in to their health.

“When patients are put on statins or any new drug, they’re seen more often by their doctor, or they themselves are paying attention to whether anything is wrong,” Strom said. “So if they have a memory problem, they’re going to notice it. Even if it has nothing to do with the drug, they’re going to blame it on the drug”

The study juxtaposed 482,542 individuals taking statin medications to 482,543 randomly selected individuals not taking any LLDs. The second control group included 26,484 users of nonstatin LLDs.

Alternate studies have already verified that statins in fact improve long-term memory, therefore, Strom said, the findings indicate short-term memory loss is not a concern either:

“You shouldn’t worry about short-term memory problems from any statins and, long-term, we know they improve memory."

Statins include atorvastatin, cerivastatin, fluvastatin, pravastatin and simvastatin, while nonstatin LLDs include cholestyramine, colestipol hydrochloride, colesevelam, clofibrate and gemfibrozil.

Strom BL, Schinnar R, Karlawish J, Hennessy S, Teal V, Bilker WB. Statin Therapy and Risk of Acute Memory Impairment. JAMA Intern Med. Published online June 08, 2015. doi:10.1001/jamainternmed.2015.2092.

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