Study Links OTC Meds to Dementia

By Jonathan Springston, Associate Managing Editor, AHC Media

Many Americans stock their medicine cabinets with over-the-counter (OTC) medications that combat symptoms of cold, flu, and allergies. But results from a recent study may cause some cold-sufferers to think twice before reaching for nighttime relief.

A research team from the University of Indiana School of Medicine, using brain imaging techniques, discovered lower metabolism and reduced brain sizes among study participants ingesting drugs known to produce an anticholinergic effect, a process that blocks acetylcholine, a nervous system neurotransmitter. Patients taking anticholinergic drugs performed worse on short-term memory and other tests such as verbal reasoning, planning, and problem solving.

Other researchers have found links between anticholinergic drugs and cognitive impairment, but University of Indiana scientists believe they are the first to study the potential underlying biology of clinical links using neuroimaging measurements of brain metabolism and atrophy.

"These findings provide us with a much better understanding of how this class of drugs may act upon the brain in ways that might raise the risk of cognitive impairment and dementia," said Shannon Risacher, PhD, assistant professor of radiology and imaging sciences and the study’s lead author in a statement. "Given all the research evidence, physicians might want to consider alternatives to anticholinergic medications if available when working with their older patients."

It’s not just OTC cold meds that are of concern, either. OTC and prescription sleep aids as well as drugs used to treat hypertension, cardiovascular disease, and COPD all produce an anticholinergic effect. However, OTC cold medications are approved only for short-term use, and this study is not specific about the dose patients ingested nor how long or how often patients took these medications.

"These findings might give us clues to the biological basis for the cognitive problems associated with anticholinergic drugs, but additional studies are needed if we are to truly understand the mechanisms involved," Risacher said.

For more articles about dementia and all the latest neurology research, be sure to read AHC Media’s monthly Neurology Alert.