title: Obstructive sleep apnea in children is associated with severity-dependent deterioration in overnight endothelial function.
abstract: BACKGROUND
  Restorative sleep is expected to promote improved endothelial function (EF) in the morning compared to the evening. However, in adults with obstructive sleep apnea (OSA) EF is not only adversely affected, but it worsens during the night. Data in pediatric OSA are scarce, and overnight changes have not been explored. Therefore, we sought to examine potential associations between pediatric OSA and overnight changes in EF.
  
  
  METHODS
  59 habitually snoring children with various degrees of sleep-disordered breathing (age range, 4-16 years) underwent EF assessment (reactive hyperemia test by EndoPAT, Itamar Medical, Israel) in the evening before and the morning after an overnight polysomnography (PSG). Two brachial occlusion periods (1 min and 5 min) also were tested. Potential associations between evening-to-morning changes in EF and polysomnographic parameters were explored.
  
  
  RESULTS
  Evening-to-morning changes in children with OSA displayed severity-dependent deterioration of EF, and occlusions lasting 1 or 5 min during the reactive hyperemia test yielded similar findings.
  
  
  CONCLUSIONS
  In children deterioration in EF during the night significantly correlated with the severity of OSA. Furthermore, the reactive hyperemia test can be reliably performed with only 60 seconds of arterial flow occlusion in children. These findings support our hypothesis that similarly to adults, sleep apnea in children results in endothelial dysfunction (ED). We speculate that pediatric OSA is less commonly associated with cardiovascular complications possibly due to the shorter duration of the syndrome.
authors: Section of Pediatric Sleep Medicine, Department of Pediatrics, Pritzker School of Medicine, Biological Sciences Division, The University of Chicago, Chicago, IL 60637-1470, USA. lgozal@peds.bsd.uchicago.edu
authors: Leila
authors: L
authors: Kheirandish-Gozal
authors: Tamar
authors: T
authors: Etzioni
authors: Rakesh
authors: R
authors: Bhattacharjee
authors: Hui-Leng
authors: HL
authors: Tan
authors: Arash
authors: A
authors: Samiei
authors: Helena
authors: H
authors: Molero Ramirez
authors: Busool
authors: B
authors: Abu Eta
authors: Giora
authors: G
authors: Pillar
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D004730:Endothelium, Vascular / Q000503:physiopathology*; D005260:Female; D006801:Humans; D000860:Hypoxia / Q000473:pathology / Q000503:physiopathology; D008297:Male; D009765:Obesity / Q000473:pathology / Q000503:physiopathology; D017286:Polysomnography; D012720:Severity of Illness Index; D020181:Sleep Apnea, Obstructive / Q000473:pathology* / Q000503:physiopathology*; D012892:Sleep Deprivation / Q000473:pathology / Q000503:physiopathology; D012894:Sleep Stages / Q000502:physiology*; D012913:Snoring / Q000473:pathology / Q000503:physiopathology