Anticholinergic Drugs May Increase Dementia Risk

Particularly Serious: Antidepressants, Drugs for Parkinson’s and Epilepsy

Researchers from the University of Nottingham in England have discovered an increased risk of dementia of almost 50% in patients aged 55 and older who were taking strong anticholinergics daily for three years or more.

Anticholinergic drugs are prescribed for chronic obstructive pulmonary disease, bladder conditions, allergies, gastrointestinal disorders, and symptoms of Parkinson's disease, among other conditions. The medicines can cause short-term confusion and memory loss, although it is uncertain whether long-term use increases the risk of dementia.

The study, published in JAMA Internal Medicine, examined the medical records of 58,769 patients with dementia and 225,574 patients without dementia, all aged at least 55 years old, between 2004 and 2016.

Findings indicated increased risks of dementia for anticholinergic drugs as a whole, but specifically for anticholinergic antidepressants, antipsychotic drugs, anti-Parkinson’s drugs, and bladder and epilepsy drugs, after accounting for other risk factors for dementia.

No increased risks were found for the other types of anticholinergic drugs such as antihistamines and gastrointestinal drugs.

Using prescription information from a 10-year period before diagnosis of dementia, or equivalent dates in control patients, the researchers assessed anticholinergic drug exposure and compared the data between the two patient groups. They also looked at prescriptions for anticholinergic drugs up to 20 years before diagnosis of dementia.

Healthcare professionals should weigh the risks and benefits of anticholinergics when prescribing the drugs, say the researchers, and should consider using alternative treatments where possible. 

As they found a greater risk for people who were diagnosed with dementia before the age of 80, the researchers suggest that anticholinergic drugs should also be prescribed with caution in middle-aged people. 

In the years prior to dementia diagnosis or the equivalent date in controls, approximately 57% of cases and 51% of controls received at least one strong anticholinergic drug, with an average of six among the cases and four among the controls. The most commonly prescribed drugs were antidepressants, anti-vertigo drugs, and bladder antimuscarinic drugs.

Source: MedicalXpress, June 24, 2019