Long-term use of benzodiazepine and related drugs has been linked to poorer quality sleep in older adults with insomnia. While they are cheap, commonly prescribed and widely available in Quebec, these drugs are also addictive: quitting cold turkey can lead to serious withdrawal symptoms, including increased risk of falls, hospitalization and cognitive issues.
A new study led by Concordia researchers published in the journal Sleep shows that use of benzodiazepine and benzodiazepine receptor agonists (BZRA) can also affect brain rhythms during sleep that are important for memory and cognitive health in adults aged between 55 and 80.
"These drugs don't even improve the sleep of the older adults using them on the long-term," says Thanh Dang-Vu , a neurologist at the Institut universitaire de gériatrie de Montréal and professor in the Department of Health, Kinesiology and Applied Physiology where he leads the Sleep, Cognition and Neuroimaging Laboratory .
"In addition to not being very safe, these drugs also make sleep quality worse in ways that may be detrimental to brain health."
Disrupted sleep architecture
The researchers studied 101 older adults categorized into three groups: good sleepers, individuals with insomnia and individuals with insomnia who chronically use benzodiazepine/BZRA, defined as using them a minimum three times per week for more than three months.
Participants' sleep was measured using an overnight polysomnography, which measured their overall sleep structure, brainwave activity and important oscillations including slow waves and sleep spindles, which are linked to memory and cognition.
"Compared to the insomnia group, the group using these sleeping pills had a lower amount of deep sleep stages," says Loïc Barbaux, PhD 2025, the study's lead author.
"These deep sleep stages, which are characterized by slower brain waves, heart rate and breathing, are very important for memory consolidation."
They also observed a decrease in the coupling between brain oscillations among individuals using benzodiazepine/BZRA. This is a neural process in which brain rhythms synchronize with each other and facilitates information processing, including memory consolidation.
Dosage also played a role in sleep alteration. The researchers found that users with higher dosages needed more time to fall asleep and took more time to reach deep sleep stage.
"These findings have led us to conclude that taking these kinds of sleeping pills worsens overall sleep architecture and brain oscillation activities," says Barbaux. "This may explain previous reports that these pills can impair some cognitive functions, which are already in decline due to aging."
Accessible alternatives are needed
Dang-Vu says benzodiazepine and BZRA may be safely and effectively used to treat anxiety and insomnia in younger adults, but mainly for short terms. He agrees with organizations including the American Geriatrics Society that recommends benzodiazepines be avoided entirely by adults over age 65.
For older adults who are chronic users, he recommends a gradual decrease of benzodiazepine consumption over several months, coupled with a cognitive behavioural therapy for insomnia program.
"If we reduce consumption progressively, we can avoid what we call rebound insomnia, which is a return of insomnia symptoms but at more intense levels. A psychological intervention can help achieve a successful withdrawal from these drugs and improve sleep quality.
"This research shows that it is time for the government and health care system to prioritize safer options for insomnia treatment that are affordable and accessible."
Read the cited paper: " Effect of chronic benzodiazepine and benzodiazepine receptor agonist use on sleep architecture and brain oscillations in older adults with chronic insomnia "
