Classification of sleep-related breathing disorders: Central sleep apnea syndrome Obstructive sleep apnea syndrome Sleep-related hypoventilation/hypoxemia syndrome Other sleep-related breathing disorders Difference between central and obstructive: clinically, most of the patients are of the mixed type; in the mixed type, more than 90% of the obstructive type is predominant; obstructive patients may have the onset of disease at any age, and most of the patients start to have the disease at the age of 40-60 years. The prevalence of obstructive patients is about 4% in males and 2% in females; purely central patients are rare; polysomnography is the gold standard for diagnosis: sleep apnea: the airflow from the mouth and nose stops for more than 10 seconds during sleep Central: no thoracic and abdominal respiratory movements during sleep apnea Obstructive: thoracic and abdominal respiratory movements during sleep apnea Sleep-related respiratory disorders: daytime somnolence. In mild cases, sleepiness is easy to fall asleep in a relaxed state (sitting watching TV, reading, watching movies, etc.) In severe cases, sleepiness may also occur during active activities (talking, driving, waiting for a green light, etc.) In extremely severe cases, sleepiness may even occur during eating and walking. Waking up at night, chest tightness and choking sensation, increased nocturnal enuresis, headache after waking up in the morning, dry mouth, cognitive impairment such as memory loss, depression, anxiety, irritability, personality change, behavioral abnormality, decreased sex drive, and heart, brain, lung, and blood vessel disease. Can be life-threatening Treatment of obstructive sleep apnea syndrome: Appropriate exercise, weight loss Weight control Smoking and alcohol cessation Avoidance of hypnotic drugs that inhibit respiratory centers Sleeping in the lateral position Medication: Efficacy not yet certain Positive airway pressure ventilation is the first choice for patients with moderate-to-severe conditions Oral appliances are appropriate for mild patients Surgical treatment: Suspension palatal pharyngoplasty, appropriate only for patients with oropharyngeal obstruction in the upper airway.