Apr 19, 2016

Commonly Used Drugs Linked to Increased Risk of Dementia

A new study offers proof of what scientists have known for a long time - anticholinergic drugs are linked with cognitive impairment and an increased risk of dementia.

Doctors should consider alternatives to anticholinergic medications when working with patients living with dementia.

Physicians might want to consider alternatives to anticholinergic medications when working with their older patients - particularly those living with dementia.

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Can commonly used over the counter drugs hurt your brain?
Conclusions and Relevance. The use of anticholinergic medications are associated with increased brain atrophy and dysfunction and clinical decline. Thus, use of AC medication among older adults should likely be discouraged if alternative therapies are available.

Older adults might want to avoid a using class of drugs commonly used in over-the-counter products such as nighttime cold medicines due to their links to cognitive impairment, a research team led by scientists at the Indiana University School of Medicine has recommended.
  • Using brain imaging techniques, the researchers found lower metabolism and reduced brain sizes among study participants taking the drugs known to have an anticholinergic effect, meaning they block acetylcholine, a nervous system neurotransmitter.
Previous research found a link between between the anticholinergic drugs and cognitive impairment and increased risk of dementia. The paper published in the journal JAMA Neurology, is believed to be the first to study the potential underlying biology of those 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," - Shannon Risacher, Ph.D., assistant professor of radiology and imaging sciences, author of the paper, “Association Between Anticholinergic Medication Use and Cognition, Brain Metabolism, and Brain Atrophy in Cognitively Normal Older Adults.”
"Given all the research evidence, physicians might want to consider alternatives to anticholinergic medications if available when working with their older patients," Dr. Risacher said.

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Drugs with anticholinergic effects are sold over the counter and by prescription as sleep aids and for many chronic diseases including hypertension, cardiovascular disease, and chronic obstructive pulmonary disease.

Here is a short list of Anticholinergic medications

  • Atropine
  • Belladonna alkaloids
  • Benzotropine mesylate (Cogentin®)
  • Dicyclomine (Bentyl®)
  • Flavoxate (Urispas®)
  • Hyosyamine (Levsinex®)
  • Oxybutynin (Ditropan®)
  • Scopolamin
  • Tolterodine (Detrol®)
  • Trihexyphenidyl HCL (Artane®)
Source: University of California San Francisco


You might not have never heard of the above medications; but,  you might have heard these of these drugs.
  • Benadryl
  • Demerol
  • Dimetapp
  • Dramamine
  • Paxil
  • Unisom 
  • VESIcare.
They are sold over the counter and by prescription as sleep aids and for chronic diseases including hypertension, cardiovascular disease and chronic obstructive pulmonary disease (COPD).

Scientists have linked anticholinergic drugs cognitive problems among older adults for at least 10 years. A 2013 study by scientists at the IU Center for Aging Research and the Regenstrief Institute found that drugs with a strong anticholinergic effect cause cognitive problems when taken continuously for as few as 60 days. Drugs with a weaker effect could cause impairment within 90 days.
  • The cognitive tests revealed that patients taking anticholinergic drugs performed worse than older adults not taking the drugs on short-term memory and some tests of executive function, which cover a range of activities such as verbal reasoning, planning, and problem solving.
Anticholinergic drug users also showed lower levels of glucose metabolism -- a biomarker for brain activity -- in both the overall brain and in the hippocampus, a region of the brain associated with memory and which has been identified as affected early by Alzheimer's disease.

The researchers also found significant links between brain structure revealed by the MRI scans and anticholinergic drug use, with the participants using anticholinergic drugs having reduced brain volume and larger ventricles, the cavities inside the brain.

The current research project involved 451 participants, 60 of whom were taking at least one medication with medium or high anticholinergic activity. The participants were drawn from a national Alzheimer's research project -- the Alzheimer's Disease Neuroimaging Initiative -- and the Indiana Memory and Aging Study.
"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," Dr. Risacher said.
Sources of information: Indiana University School of Medicine, CNN, Regenstrief Institute, IU Center for Aging Research, University of California San Francisco

Association Between Anticholinergic Medication Use and Cognition, Brain Metabolism, and Brain Atrophy in Cognitively Normal Older Adults
JAMA Neurol. Published online April 18, 2016. doi:10.1001/jamaneurol.2016.0580

Anticholinergics decrease acetylcholine activity to balance out the production of dopamine and acetylcholine. They are used to treat incontinence, depression and sleep disorders. Medications with strong anticholinergic effects, such as antihistamines that cause drowsiness, are well known for causing acute cognitive impairment in individuals with dementia and may cause confusion and hallucinations. Furthermore, with the cholinergic deficit in some forms of dementia, they could potentate (increase) this deficit and antagonize any cholinesterase inhibiting medications.

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Additional investigators contributing to this research were Brenna C. McDonald, Eileen F. Tallman, John D. West, Martin R. Farlow, Fredrick W. Unverzagt, and Sujuan Gao, IU School of Medicine; Malaz Boustani, IU School of Medicine, Regenstrief Institute and Eskenazi Health; Paul K. Crane, University of Washington; Ronald C. Petersen and Clifford R. Jack Jr., Mayo Clinic; William J. Jagust, University of California-Berkeley; Paul S. Aisen, University of Southern California, San Diego; Michael W. Weiner, University of California-San Francisco; Andrew J. Saykin, IU School of Medicine for the Alzheimer’s Disease Neuroimaging Initiative.

Data collection and sharing for this project was funded by the Alzheimer's Disease Neuroimaging Initiative (ADNI) (National Institutes of Health Grant U01 AG024904) and DOD ADNI (Department of Defense award number W81XWH-12-2-0012).