May 11, 2023 – People with sleep apnea who spend less time in deep sleep are more likely to have brain health problems that could lead to dementia, Alzheimer’s disease, or a stroke, a new study shows.
Previous research has shown a connection between sleep problems and cognitive decline and dementia, and this latest study sought to explore potential causes. Researchers from the Mayo Clinic examined two measures of brain health in people with sleep apnea. Using pictures of the brain from MRIs, they could detect signs of aging in the brain’s white matter and nerve connections.
The findings were not conclusive enough to allow researchers to say that sleep apnea causes cognitive decline or stroke, but are sound enough to point scientists toward further exploration.
In a statement, researcher Diego Z. Carvalho, MD, said the findings were “important since there is no treatment for these changes in the brain, so we need to find ways to prevent them from happening or getting worse.”
The study was published Wednesday in Neurology, the medical journal of the American Academy of Neurology, and included 140 people diagnosed with sleep apnea whose average age was 73 years old. The researchers analyzed data from MRIs of the people’s brains and from overnight sleep studies.
Reduced deep sleep (also called slow-wave or non-REM stage 3) was directly related to how old people’s brains appeared to be. The less time someone spent in deep sleep, the older their brains looked.
The people in the study had the most common type of sleep apnea, called obstructive sleep apnea. The condition results in blocked airflow into or out of the mouth or nose, even when someone is trying to breathe.