title: Sleep-disordered breathing, systemic adipokine secretion, and metabolic dysregulation in overweight and obese children and adolescents.
abstract: Obstructive sleep apnea (OSA) is common among overweight and obese children, and it is an independent risk factor for developing metabolic syndrome. However, the mechanisms linking OSA and metabolic syndrome are still unclear, but a role for adipose tissue dysfunction caused by intermittent hypoxia has been suggested. Therefore, the goal of this study was to investigate the relationship between OSA and systemic adipokine concentrations in overweight and obese children.
  
  
  
  We included 164 overweight and obese children in a tertiary center and distributed them in groups based on their obstructive apnea-hypopnea index (111 controls, 28 mild OSA, 25 moderate-to-severe OSA). All subjects underwent polysomnography and a blood sample was taken to determine leptin, adiponectin, tumor necrosis factor alpha, and interleukin-6 levels.
  
  
  
  No significant differences were found in adipokine levels between subjects with or without OSA. Leptin correlated with oxygen desaturation index (r = -0.17, p = 0.03), adiponectin correlated with mean oxygen saturation (r = 0.24, p = 0.002) and with the percentage of sleep time with an oxygen saturation >95% (r = 0.25, p = 0.001). However, these associations did not persist after correction for adiposity. No correlations between interleukin-6 and tumor necrosis factor alpha, and OSA severity were found.
  
  
  
  These results suggest that serum adipokine levels are mostly dependent on central obesity, while they are not influenced by OSA in an obese pediatric population.
authors.affiliation: Laboratory of Experimental Medicine and Pediatrics, University of Antwerp, Antwerp, Belgium. Electronic address: Annelies.vaneyck@uantwerpen.be.
authors.forename: Annelies
authors.initials: A
authors.lastname: Van Eyck
authors.affiliation: Laboratory of Experimental Medicine and Pediatrics, University of Antwerp, Antwerp, Belgium; Department of Pediatrics, Antwerp University Hospital, Edegem, Belgium.
authors.forename: Kim
authors.initials: K
authors.lastname: Van Hoorenbeeck
authors.affiliation: Laboratory of Experimental Medicine and Pediatrics, University of Antwerp, Antwerp, Belgium.
authors.forename: Benedicte Y
authors.initials: BY
authors.lastname: De Winter
authors.affiliation: Laboratory of Experimental Medicine and Pediatrics, University of Antwerp, Antwerp, Belgium; Department of Endocrinology, Diabetology and Metabolism, Antwerp University Hospital, Edegem, Belgium.
authors.forename: Luc
authors.initials: L
authors.lastname: Van Gaal
authors.affiliation: Laboratory of Experimental Medicine and Pediatrics, University of Antwerp, Antwerp, Belgium; Department of Pulmonology, Antwerp University Hospital, Edegem, Belgium.
authors.forename: Wilfried
authors.initials: W
authors.lastname: De Backer
authors.affiliation: Laboratory of Experimental Medicine and Pediatrics, University of Antwerp, Antwerp, Belgium; Department of Pediatrics, Antwerp University Hospital, Edegem, Belgium.
authors.forename: Stijn L
authors.initials: SL
authors.lastname: Verhulst
mesh_terms: D054392:Adipokines / Q000097:blood*; D000293:Adolescent; D002648:Child; D005260:Female; D006801:Humans; D008297:Male; D024821:Metabolic Syndrome / Q000453:epidemiology* / Q000209:etiology; D009765:Obesity / Q000097:blood*; D050177:Overweight / Q000097:blood*; D015995:Prevalence; D020181:Sleep Apnea, Obstructive / Q000097:blood* / Q000150:complications
chemical_list: D054392:Adipokines
keywords: Adiponectin; Interleukin-6; Leptin; Metabolic syndrome; Obstructive sleep apnea; Tumor necrosis factor alpha