title: Rhythm disturbances in childhood obstructive sleep apnea during apnea-hypopnea episodes.
abstract: BACKGROUND
  Obstructive sleep apnoea (OSA) can result in cardiovascular complications. Nocturnal arrhythmias are reported up to 50% of adult OSA patients. Arrhythmias and heart rate variability in children with OSA have not been well studied.
  
  
  OBJECTIVE
  We sought to study rhythm disturbances in childhood OSA and also to analyze the relationship of heart rate variability to the severity of OSA in children.
  
  
  METHODS
  In a retrospective cross sectional study, records of children aged < 15 years with history of snoring and suspected OSA, who had undergone polysomnography (PSG) for first time were analyzed. The cardiac rhythm and heart rate variability were studied during PSG.
  
  
  RESULTS
  A total of 124 patients diagnosed with OSA were grouped into mild (n = 52), moderate (n = 30), and severe (n = 42) OSA. During PSG, all had sinus arrhythmias and only three patients had premature atrial contractions (PACs). The standard deviation of heart rate (SD-HR) during rapid eye movement (REM) sleep in severe OSA (9.1 ± 2.4) was significantly higher than SD-HR in mild OSA (7.5 ± 1.3, P < 0.0001). The maximum heart rate (max-HR) during REM-sleep in severe OSA (132.1 ± 22.1) was significantly higher than the max-HR in mild OSA (121.3 ± 12.6 bpm, P = 0.016).
  
  
  CONCLUSIONS
  There was no significant arrhythmia in children with OSA during their sleep. Heart rate variability correlated with the severity of OSA.
authors.affiliation: Department of Pediatrics, Faculty of Medicine, Ramathibodi Hospital, Mahidol University, Bangkok, Thailand.
authors.forename: Anant
authors.initials: A
authors.lastname: Khositseth
authors.forename: Jittamas
authors.initials: J
authors.lastname: Chokechuleekorn
authors.forename: Teeradej
authors.initials: T
authors.lastname: Kuptanon
authors.forename: Anchalee
authors.initials: A
authors.lastname: Leejakpai
keywords: Arrhythmia; children; obstructive sleep apnea