Child patients Adult patients Age of prevalence Preschool children 3-6 years old Young adults 30-50 years old Gender Male to female ratio is about the same Male predominant, some postmenopausal women Main causes Tonsils, especially adenoid hypertrophy Obesity, small jaw deformity, muscle laxity Weight Developmental delay, normal weight or obesity Obesity predominant Complications Daytime sleepiness is rare, with enuresis, hyperactivity, irritability Daytime sleepiness is common, cognitive function Hypovolemia, cardiovascular Developmental delay, behavioral abnormalities Respiratory disorders, death by asphyxia during sleep Respiratory disturbances Obstructive hypoventilation with intermittent apnea episodes, predominantly obstructive hypoventilation with intermittent apnea Predominantly hypoventilation Predominantly apnea Sleep structure Basically normal 3+4 deep sleep and REM sleep reduced or missing wake Spontaneous awakenings are high and rarely accompanied by respiratory disturbances Most end-stage apnea is accompanied by awakening Surgical treatment Most tonsils and adenoids can be cured by removal of tonsils and adenoids Modified H-UPPP, nasal endoscopy, or combined surgical treatment depending on the site of obstruction Positive pressure ventilation is used in a small number of cases, and most patients have good outcomes (CPAP)