Cognitive Labs

Unusual swelling within some of the brain’s neurons might be responsible for the reversible memory loss and impaired thinking ability experienced by some patients who take cholesterol-lowering statins, researchers from the University of Arizona (UA) claim in a new study.

The side effects, which have been observed by both physicians and US Food and Drug Administration (FDA) personnel, could be caused by this phenomenon – which the researchers have dubbed the “beads-on-a-string” effect. They compare it to a “traffic jam” of sorts, in which changes in the morphology of the neurons disrupt their function.

According to lead investigator Linda L. Restifo, she and her colleagues are not entirely certain why these so-called beads form, but they are confident that further detailed analysis of them will shed new light on why some individuals experience cognitive decline while taking these widely-prescribed drugs.

“What we think we’ve found is a laboratory demonstration of a problem in the neuron that is a more severe version for what is happening in some peoples’ brains when they take statins,” Restifo, a UA professor of neuroscience,neurology and cellular and molecular medicine, said in a statement. Her team’s research has been published in the peer-reviewed journal Disease Models & Mechanisms.

The researchers, citing clinical reports, explain doctors often tell statin users that cognitive disturbances experienced while taking the medications were the result of aging or other effects. However, they state their research provides new evidence of a link between cognitive decline and a negative response to the cholesterol-lowering drug, and removing statins causes the disappearance of the beads-on-a-string phenomenon.

Restifo’s team plans to continue their research in order to establish exactly how DNA could play a role in the formation of the beads, and whether or not there are genetic causes for the hypersensitivity to statins in some individuals. They believe potential genetic differences could possibly directly involve the neurons themselves, or alternatively the interaction between the drug and the person’s blood-brain barrier.

“This is a great first step on the road toward more personalized medication and therapy. If we can figure out a way to identify patients who will have certain side effects, we can improve therapeutic outcomes,” said David M. Labiner, the head of the UA department of neurology.

The team is now attempting to secure additional funding in the form of pending grants. Restifo said they hope to complete genetic studies as part of their future research. If they are able to do so, the goal of their continued research would be “to come up with a predictive test so that a patient with high cholesterol could be tested first to determine whether they have a sensitivity to statins,” Restifo concluded.