Obstructive Sleep Apnea Common in People With Thinking, Memory Problems

March 3, 2021
Jill Murphy, Associate Editor

Cognitive impairment includes memory and thinking problems that affect concentration, decision making and learning new things, which increases as people grow older.

Obstructive sleep apnea is common in people with cognitive impairment, following previous research that people with this sleep disorder have an increased risk of developing cognitive impairment and Alzheimer disease, according to a study that will be presented virtually at the American Academy of Neurology's 73rd Annual Meeting from April 17 to 22, 2021.

Cognitive impairment includes memory and thinking problems that affect concentration, decision making and learning new things, which increases as people grow older, according to the study authors.

"Better sleep is beneficial to the brain and can improve cognitive skills. Yet in our study, we found that over half of the people with cognitive impairment had obstructive sleep apnea," said study author Mark I. Boulos, MD, of the University of Toronto, Canada, and member of the American Academy of Neurology, in a press release. "We also found that those with the sleep disorder had lower scores on thinking and memory tests. Fully understanding how obstructive sleep apnea affects this population is important because with treatment, there is potential to improve thinking and memory skills as well as overall quality of life."

The study included 67 people with an average age of 73 years who had cognitive impairment, with participants completing questionnaires on sleep, cognition, and mood. In addition, they completed a 30-point cognitive assessment to determine their level of cognitive impairment.

Questions included identifying the date and the city they were in and repeating words they had been asked to remember earlier in the test. Scores on the test range from 0 to 30, with a score of 26 or higher being considered normal, 18 to 25 signifies mild cognitive impairment and 17 or lower signifies moderate to severe cognitive impairment, according to the study authors.

Further, participants were given at-home sleep apnea tests to determine whether they had obstructive sleep apnea. The at-home test uses a monitor to track breathing patterns and oxygen levels during sleep.

The research team found that 52% of study participants had obstructive sleep apnea. People with the sleep disorder were 60% more likely to score lower on the cognitive test than people who did not have sleep apnea. Additionally, people with sleep apnea had an average score of 20.5 compared to an average score of 23.6 for the people without the sleep disorder, according to the study authors.

The researchers also found that the severity of obstructive sleep apnea corresponded with the degree of cognitive impairment as well as the quality of sleep for participants, including sleep time, how quickly they fell asleep, the efficiency of their sleep, and how often they awoke at night.

"People with cognitive impairment should be assessed for obstructive sleep apnea because it can be treated by using a continuous positive airway pressure (CPAP) machine that helps keep the airway open at night," Boulos said in a press release. "However, not everyone who tries CPAP chooses to regularly use the therapy, and this may be a bigger challenge to people with thinking and memory problems. Future research should be directed toward determining ways to diagnose and manage the disease that are efficient and easy to use in people with cognitive impairment."

REFERENCE

Study: Treatable sleep disorder common in people with thinking and memory problems. EurekAlert! https://www.eurekalert.org/pub_releases/2021-02/aaon-sts021821.php. Published February 28, 2021. Accessed March 1, 2021.