A common class of drugs known as anticholinergics, used to treat a number of illnesses such as depression and Parkinson’s disease, may also increase a patient’s risk of dementia by 30 percent, according to a new study published in the British Medical Journal. Anticholinergic drugs are also used to treat gastrointestinal disorders, urinary incontinence, epilepsy and allergies. It is estimated that 20 to 50 percent of Americans 65 and older take at least one anticholinergic medication.
The research team analyzed more than 27 million prescriptions, as recorded in the medical records of 40,770 patients ages 65 to 99 who were diagnosed with dementia, and compared them with the records of 283,933 older adults without dementia. The researchers found greater incidences of dementia among patients prescribed anticholinergic antidepressants, urological medications and Parkinson's disease medications than among older adults who were not prescribed these drugs. These incidences of dementia were found up to 20 years after exposure to the drugs. It was noted that anticholinergic drugs used for gastrointestinal and cardiovascular issues such as asthma are not associated with later incidences of dementia.
“Many people use anticholinergic drugs at some point in their lives, and many are prescribed to manage chronic conditions leading to potentially long exposures,” researchers stated. “Clinicians should continue to be vigilant with respect to the use of anticholinergic drugs and should consider the risk of long-term cognitive effects, as well as short-term effects, associated with specific drug classes when performing their risk-benefit analysis.”