Obstructive sleep apnea (OSA) is a common sleep disorder that occurs when the muscles in the throat relax too much during sleep, blocking airflow to the lungs. This can cause loud snoring, restless sleep, daytime fatigue, and morning headaches.
While OSA is often linked to other health issues like heart disease and diabetes, a new study shows that it may also cause cognitive decline—even in otherwise healthy, non-obese middle-aged men.
Researchers from the UK, Germany, and Australia found that men with OSA performed worse on tests measuring memory, attention, impulse control, and social cognition. These deficits were present even in those without other health conditions, suggesting that OSA itself may be enough to impact brain function.
The study involved 27 men between the ages of 35 and 70 who had been newly diagnosed with mild to severe OSA. Unlike most OSA patients, these men had no other medical conditions. A smaller control group of seven men without OSA, matched for age, weight, and education, was also studied.
To assess their sleep and brain function, researchers used a WatchPAT test to confirm OSA diagnoses and a video-polysomnography to track breathing during sleep. They also measured brain waves using electroencephalography (EEG), along with blood oxygen levels, heart rate, and movement.
The results showed that men with severe OSA had worse cognitive performance than those with mild OSA, who in turn performed worse than the control group.
Previous research had linked cognitive decline in OSA patients to related conditions like high blood pressure and diabetes. However, this study suggests that OSA itself—without any other health issues—may be enough to cause cognitive deficits.
Scientists believe that repeated drops in oxygen levels, changes in blood flow to the brain, disrupted sleep patterns, and brain inflammation could explain why OSA leads to cognitive decline.
However, more research is needed to fully understand the connection and to explore whether OSA combined with other health problems could make cognitive decline even worse.
These findings highlight the importance of diagnosing and treating sleep apnea early. Left untreated, OSA may lead to long-term brain changes that could increase the risk of dementia and other cognitive disorders.
The study was conducted by Ivana Rosenzweig and colleagues and published in Frontiers in Sleep.
If you care about dementia, please read studies about low choline intake linked to higher dementia risk, and how eating nuts can affect your cognitive ability.
For more information about brain health, please see recent studies that blueberry supplements may prevent cognitive decline, and results showing higher magnesium intake could help benefit brain health.
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