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Medical Care
Senior Health

Anticholinergic Drugs Linked to Risk Of Pneumonia in the Elderly

In a study of more than 3,000 older patients living in the community, not in nursing homes, taking commonly used medications with anticholinergic effects was associated with a significantly higher risk for developing pneumonia. The study was done by the Group Health Research Institute in Seattle, Washington and published in March 2015 the Journal of the American Geriatrics Society.

A release from the institute quotes senior author Sascha Dublin, MD, PhD, a Group Health physician and Group Health Research Institute (GHRI) associate investigator, as saying “Our study is the first to address whether oral anticholinergic medications affect the risk of pneumonia in older people. This is important because so many older people use these medications, and pneumonia is such a common cause of illness and death in this age group.” Dr. Dublin is also an affiliate associate professor of epidemiology at the University of Washington School of Public Health.

The release notes that a recent University of Washington-Group Health study linked cumulative use of anticholinergic medications to a higher risk for dementia. Dr. Dublin was a coauthor of that study of a different group of Group Health patients. Anticholinergic medications block the neurotransmitter called acetylcholine in the brain and body, and that can cause many side effects, including sedation, confusion, constipation, vision changes, retaining urine, and dry mouth and eyes.


In the new study, more than 1,000 Group Health patients aged 65 to 94 years who developed pneumonia were compared with a control group of more than 2,000 patients who were matched to the first group by age, sex, and year and didn’t get the disease.

“We found a link between both acute and chronic use of anticholinergic medications and a much higher risk for developing pneumonia,” said first author Kathleen J. Paul, MD, MPH, a third-year resident in family medicine at Group Health. Acute use meant filling at least one prescription within 90 days before the pneumonia diagnosis, and chronic use was filling at least three prescriptions in the prior year. One of the study’s strengths is that it used Group Health’s pharmacy records, which include substantial over-the-counter use, to determine that the patients actually filled their prescriptions.

Prior reports about these same patients linked a higher risk for pneumonia to use of opioids–but not benzodiazepines, statins, proton pump inhibitors, histamine blockers, or angiotensin-converting enzyme inhibitors.