Recently, polysomnography and positive pressure devices (a device that delivers constant pressure of air to a person who has difficulty breathing during sleep) have begun to be covered by insurance, and interest in sleep disorder treatment is growing. Obstructive sleep apnea, one of the most common sleep disorders, is predominantly in hypertensive patients.
“High blood pressure is one of the main causes of stroke, and regarding 50% of hypertensive patients suffer from obstructive sleep apnea,” said Jo Seong-rae, a neurologist at Yuseongseon Hospital’s Stroke Center. There are also reports of obstructive sleep apnea.”
Obstructive sleep apnea is diagnosed when you breathe less than 10 seconds or stop breathing more than 5 times per hour during sleep. Obstructive sleep apnea can also be caused by a thick neck, small jaw, and enlarged tonsils, but male, old age, drinking, smoking, diabetes, and obesity are the main risk factors. These factors overlap to a large extent with those that can induce stroke.
If you don’t breathe while you sleep, your oxygen saturation decreases. At this time, the brain wakes up some of the consciousness and allows you to breathe once more. This raises blood pressure and blood sugar levels at night, and increases the risk of arrhythmia, one of the strongest causes of stroke.
When you are not breathing during sleep, the blood vessels in your brain constrict. As a result, cerebral blood flow changes and the function of vascular endothelial cells (a tissue that plays an important role in vascular elasticity and hemostasis) decreases. Then, no matter how long you sleep, it is difficult to get a good night’s sleep, so you will continue to feel drowsy during the day and your work efficiency will decrease. Specialist Jo Seong-rae said, “Sleep apnea of moderate or higher severity (when you breathe less than 10 seconds or stop breathing more than 15 times per hour during sleep) causes changes in brain tissue and cerebral infarction without your knowledge, increasing the risk of vascular dementia. It can also speed up the development of atherosclerosis in the carotid artery that supplies blood to the body.”
There is also a report that sleep apnea is found in 50 to 70% of patients with acute cerebral infarction or transient cerebral ischemia (a disease in which the blood supply to the brain is temporarily blocked and then resumes, causing the brain to fall into a state of instantaneous shock). Jo Sung-rae, a neurologist at Yuseongseon Hospital’s Stroke Center, said, “The indicator that shows how often sleep apnea and hypopnea occur per hour is called AHI (apnea-hypopnea index). “When a stroke occurs in patients with sleep apnea, recovery may be delayed and the effectiveness of rehabilitation treatment may be lower than in patients without sleep apnea,” he said. .
In some studies, sleep apnea as well as sleep duration are known to be associated with cerebral infarction. Although the optimal amount of sleep varies from person to person, in the case of Koreans, it is generally known that regarding 7 hours a day. The risk of a stroke increases by 44% if you sleep for less than 5 hours per night. If you sleep too little, the sympathetic nervous system is activated too much, which increases the risk of high blood pressure and diabetes, and changes fat metabolism, which can lead to obesity and hyperlipidemia. In addition, lack of sleep increases the secretion of food-stimulating hormone and may lead to decreased daily activities, which may affect weight gain. Specialist Jo Seong-rae said, “Sleeping too much is also bad for health, and excessive sleep can increase the risk of cerebral infarction by causing carotid arteriosclerosis, arrhythmias, and changes in brain tissue. The risk increases by regarding 50%. It is important to keep 7 to 8 hours of sleep a day, which is known as the proper amount of sleep for Koreans.”
Among modern office workers, there are many people who sleep irregularly due to various reasons such as night shifts and shift work. Studies of these people have found higher rates of obesity, high blood pressure, diabetes, cardiovascular disease and mortality. A large-scale study of nurses who worked shifts also showed that the risk of cerebral infarction was higher than that of the general population. People in these occupations need basic management of stroke risk factors. Of course, to prevent stroke, management and prevention of high blood pressure, diabetes, hyperlipidemia, and heart disease is the most important, and it is also essential to avoid alcohol, stop smoking, and manage obesity. However, you should not neglect to manage the quality and quantity of sleep.
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