A long breath of sleep at night may be caused by obstructive sleep apnea hypoventilation syndrome, among other things. Obstructive sleep apnea hypoventilation syndrome: refers to the apnea and hypoventilation caused by repeated collapse and obstruction of the upper airway during sleep, which can directly lead to sleep structure disorders, hypoxemia, hypercapnia, significant changes in intrathoracic pressure and increased sympathetic nerve activity Patients are often accompanied by snoring, frequent oxygen saturation, daytime drowsiness, and inattention. Patients with apnea hypoventilation syndrome experience apnea at night when they sleep due to a decreased ability to maintain open airway function. Therefore when the patient resumes breathing, he or she will deepen his or her breath to maintain normal ventilation, which can manifest as a long breath of sleep at night. Treatment can be firstly through weight loss, quitting smoking and alcohol, establishing the habit of sleeping in the side position; continuous positive pressure ventilation treatment; wearing an intraoral device inside the mouth during sleep to enlarge the airway; surgical treatment, such as correction of deviated nasal septum, excision of enlarged adenoids and tonsils in children, and so on. If you have a long breath during sleep at night, it is recommended that you go to a regular hospital in time to find out the cause, and then receive standardized treatment from a professional doctor.