Which symptoms occur and when does sleep apnea require therapy?
Often, bed neighbors become aware of their partner’s restless sleep with pauses in breathing that end with a snoring sound or sigh, and irregular loud snoring. The breathing rhythm is disturbed.
Cause of sleep apnea syndrome
In more than 90% of cases, the cause of sleep apnoea syndrome is located in the upper airways: the throat of the affected person narrows with the beginning of the deep sleep phase because the pharyngeal wall musculature slackens and thus the access of the upper airways is partially blocked. This phenomenon occurs preferentially in overweight patients and is intensified by the consumption of alcohol, smoking or the use of tranquilizers. Diseases of the upper airways such as nasal polyps or an inclined nasal septum (nasal septum curvature) can promote the development of sleep apnoea syndrome, as they favour mouth breathing.
Snoring sounds are caused by the collapse of the upper airways, so that patients with sleep apnoea syndrome are practically always heavy snorers. Snorers who are very tired during the day should therefore be examined for sleep apnoea syndrome. Sleep apnoea syndrome is caused in less than 10% of cases by central malfunctions of breathing during sleep or is the result of a chronic lung disease.
The mostly obese sleep apnea patients often have additional concomitant diseases such as cardiac arrhythmia, a narrowing or complete blockage of the coronary arteries (coronary heart disease) or a pumping weakness of the heart (heart failure).The high blood pressure, which about 50% of patients with sleep apnea syndrome have, is the result of increased activity of the stress-mediating nervous system, which releases more of the hormones adrenaline and noradrenaline: Due to the apnoea phases during sleep, the patient breathes less oxygen and the body threatens to get into a situation of oxygen deficiency. The organism must therefore be driven to work harder to breathe. The stress-mediating nervous system does this by sending an alarm to the body through the norepinephrine and adrenaline.
However, the subsequent increased work of breathing is often not efficient, so that a wake-up reaction (micro arousal) finally occurs, which enables normal and efficient breathing with sufficient oxygen intake again. Waking up at night usually remains unconscious, but it causes sleep fragmentation and disturbs the nightly recovery, so that patients are very tired during the day and even sleep attacks can occur. In addition, a faster pulse during sleep and heart rhythm disturbances can be observed in sleep apnoea syndrome patients.
