Study Shows Popular Sleep Aids, Bladder Meds May Contribute to Dementia

A study released this week by the Journal of the American Medical Association shows patients over age 65 who take popular sleep aid medications may face higher chances of developing dementia.

It’s not the first study to produce such results, however, it is the first to isolate the risk to the drugs themselves, instead of underlying risk factors in patients taking them. Also, what were initially thought to be temporary cognitive side effects may now actually be permanent.

The study was headed by Dr. Shelly Gray, a researcher at the University of Washington. Gray’s team reviewed data from almost 3,500 subjects over the age of 64 who were taking different forms of anticholinergic medications. These drugs, which block a neurotransmitter called acetylcholine, include oxybutynin, used to treat overactive bladder, antidepressant drugs like doxepin used for sleep aid and anxiety; and antihistamines like chlorpheniramine.

Studies indicate up to 37% of those older than 65 take anticholinergic drugs. They are known by brand names like the bladder meds Ditropan, Gelnique and Oxytrol; sleep aids Silenor, Zonalon and Prudoxin; and antihistamines Chlor-Trimeton, Chlor-Tab and Aller-Chlor.

Records were only reviewed for those patients that didn’t previously have dementia. In the following seven years on average, however, more than 23% of them were diagnosed with dementia, and nearly 19% developed Alzheimer's disease.

A patient’s dementia risk was also tied to how much of an anticholinergic drug they had taken over time. The greater the dose – the greater the risk. Those who used 10 milligrams of doxepin each day for three years were at an elevated risk, as were those who took 4 milligrams of chlorpheniramine, or 5 milligrams of oxybutinin every day.

While Gray said scientists have known for years that even small doses of these drugs can lead to cognitive impairment, it was thought that the effects subsided when patients stopped taking them.

But the new research showed higher doses of the drugs can lead to dementia, which is permanent.

DrugNews will continue to track any additional research on the cognitive impairment effects of sleep aids, bladder medications and antihistamines. Contact us for more information or any questions.