Obstructive sleep apnea (OSA) is a common sleep disorder that affects millions of people worldwide. It happens when the muscles in the throat relax too much during sleep, causing the airway to become blocked. This blockage stops air from getting into the lungs, leading to interrupted breathing.
People with OSA often experience loud snoring, restless sleep, daytime fatigue, and morning headaches. These symptoms can be difficult for both the person with OSA and their partner, as sleep is often disrupted throughout the night.
New research conducted by scientists from the UK, Germany, and Australia has found that OSA may be linked to cognitive decline, even in middle-aged men who are otherwise healthy and not overweight.
This finding is surprising because cognitive problems are often associated with health issues like obesity, heart disease, or diabetes. However, the study showed that OSA alone could lead to problems with memory, decision-making, and even social understanding.
The study included 27 men between the ages of 35 and 70 who had been newly diagnosed with mild to severe OSA. None of the men had any other health conditions like heart disease, diabetes, or depression, which are often seen in people with OSA.
Because most people with sleep apnea have these additional health problems, finding this group of otherwise healthy men was rare and valuable for the study. To compare their findings, the researchers also included seven men of similar age, weight, and education levels who did not have OSA.
To confirm the presence of OSA, the researchers used a test called WatchPAT. This device tracks how well a person breathes while they sleep. They also used a video-polysomnography test to monitor how well the men were breathing, how often they stopped breathing, and how much oxygen was in their blood.
They measured brain activity during sleep using electroencephalography (EEG) and kept track of heart rate, breathing patterns, and even movements of the eyes and legs.
The results were clear: men with severe OSA performed worse on tests of cognitive function compared to the men without OSA. Even those with mild OSA showed some cognitive difficulties, though not as severe as those with the more serious form of the disorder.
The areas where these men struggled the most included executive functioning, which is the ability to make decisions and solve problems, and visuospatial memory, which is important for understanding spaces and locations.
They also had trouble with sustained attention, quick thinking, and controlling their impulses. Surprisingly, the study also found that OSA affected their social cognition, making it harder for them to understand social cues and react appropriately in conversations.
The researchers believe these problems are caused by several factors linked to OSA. One major issue is low oxygen levels during sleep. Because breathing is interrupted, the brain does not get enough oxygen at regular intervals. At the same time, carbon dioxide builds up in the blood, which can also harm brain function.
Sleep fragmentation—when sleep is repeatedly interrupted—prevents the brain from going through the full sleep cycles needed for rest and repair. The team also suspects that OSA may lead to inflammation in the brain, which can further damage brain cells and affect cognitive health.
This study challenges earlier beliefs that the cognitive decline seen in people with OSA was mainly due to co-existing health conditions like heart disease or diabetes. The researchers argue that OSA alone is enough to cause these problems.
However, they also note that the exact way OSA leads to cognitive decline is still not fully understood. More research is needed to see if other health problems add to the cognitive damage caused by OSA.
These findings highlight the importance of diagnosing and treating OSA early. Many people may not even realize they have sleep apnea, as the main symptom—snoring—often goes unnoticed unless a partner points it out. However, addressing OSA can prevent not just poor sleep and fatigue, but also long-term cognitive issues that could affect memory, decision-making, and social interactions.
To protect brain health and prevent cognitive decline, it’s important to follow healthy lifestyle habits. Regular physical exercise can improve blood flow to the brain and reduce inflammation. A balanced diet rich in fruits, vegetables, whole grains, and lean proteins supports brain health, and foods with omega-3 fatty acids, like fish and nuts, are especially beneficial.
Mental activities like reading, puzzles, and learning new skills can keep the brain sharp. Getting enough quality sleep is also crucial, as it allows the brain to rest and repair. Additionally, managing chronic health conditions like high blood pressure and diabetes can help lower the risk of cognitive decline. Finally, avoiding smoking and limiting alcohol can also protect brain health.
This study, led by Ivana Rosenzweig and her team, was published in Frontiers in Sleep. Their research not only shows the impact of OSA on cognitive health but also emphasizes the need for early detection and treatment.
For those who snore loudly, feel overly tired during the day, or struggle with memory and focus, it may be worth discussing OSA with a healthcare provider. Addressing the condition early could not only improve sleep but also protect brain health in the long term.
If you care about dementia, please read studies that eating apples and tea could keep dementia at bay, and Olive oil: a daily dose for better brain health.
For more health information, please see recent studies what you eat together may affect your dementia risk, and time-restricted eating: a simple way to fight aging and cancer.
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