<unk>  is a sleep disorder characterized by the narrowing of the<unk>  that can cause disruptions to sleep. The symptoms include unrefreshing sleep, fatigue, sleepiness, chronic insomnia, and difficulty concentrating.<unk>  can be diagnosed by polysomnograms capable of detecting Respiratory Effort-related Arousals. It can be treated with lifestyle changes, orthodontics, surgery, or CPAP therapy.<unk>  is considered a variant of sleep apnea, although some scientists and doctors believe it to be a distinct disorder.
Upper airway resistance syndrome
Central hypoventilation syndrome
Obesity hypoventilation syndrome
Hyperventilation syndrome
Reactive airway disease
Eustachian tube dysfunction
Cardiac asthma
Yokkaichi asthma