title: Sleep architecture and obstructive sleep apnea in obese children with and without metabolic syndrome: a case control study.
abstract: OBJECTIVE
  Obesity and biochemical parameters of metabolic disorders are both closely related to obstructive sleep apnea (OSA). The aim of this study was to compare sleep architecture and OSA in obese children with and without metabolic syndrome.
  
  
  METHODS
  Forty-two children with metabolic syndrome were selected as case group and 38 children without metabolic syndrome were matched for age, sex, and BMI as control group. The standardized Persian version of bedtime problems, excessive daytime sleepiness, awakenings during the night, regularity and duration of sleep, snoring (BEARS) and Children's Sleep Habits Questionnaires were completed, and polysomnography (PSG) was performed for all study subjects. Scoring was performed using the manual of American Academy of Sleep Medicine for children. Data were analyzed using chi-square test, T test, Mann-Whitney U test, and logistic regression analysis.
  
  
  RESULTS
  Non-rapid eye movement (NREM) sleep and N1 stage in the case group were significantly longer than the control group, while REM sleep was significantly shorter. Waking after sleep onset (WASO) was significantly different between two groups. Severe OSA was more frequent in the control group. Multivariate logistic regression analysis showed that severe OSA (OR 21.478, 95 % CI 2.160-213.600; P = 0.009) and REM sleep (OR 0.856, 95 % CI 0.737-0.994; P = 0.041) had independent association with metabolic syndrome.
  
  
  CONCLUSIONS
  Obese children with metabolic syndrome had increased WASO, N1 sleep stage, and severe OSA. But the results regarding sleep architecture are most likely a direct result of OSA severity. More longitudinal studies are needed to confirm the association of metabolic syndrome and OSA.
authors.affiliation: Children Growth Research Center, Qazvin University of Medical Sciences, Qazvin, Iran.
authors.forename: Shabnam
authors.initials: S
authors.lastname: Jalilolghadr
authors.affiliation: Metabolic Diseases Research Center, Qazvin University of Medical Sciences, Qazvin, Iran.
authors.forename: Zohreh
authors.initials: Z
authors.lastname: Yazdi
authors.affiliation: Children Growth Research Center, Qazvin University of Medical Sciences, Qazvin, Iran.
authors.forename: Manoochehr
authors.initials: M
authors.lastname: Mahram
authors.affiliation: Qazvin University of Medical Sciences, Qazvin, Iran.
authors.forename: Farkhondeh
authors.initials: F
authors.lastname: Babaei
authors.affiliation: Metabolic Diseases Research Center, Qazvin University of Medical Sciences, Qazvin, Iran.
authors.forename: Neda
authors.initials: N
authors.lastname: Esmailzadehha
authors.affiliation: Gaziantep Medical University, Gaziantep, Turkey.
authors.forename: Hoormehr
authors.initials: H
authors.lastname: Nozari
authors.affiliation: Metabolic Diseases Research Center, Qazvin University of Medical Sciences, Qazvin, Iran. drfa_saffari@yahoo.com.
authors.forename: Fatemeh
authors.initials: F
authors.lastname: Saffari
mesh_terms: D000293:Adolescent; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D015897:Comorbidity; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008297:Male; D024821:Metabolic Syndrome / Q000150:complications* / Q000453:epidemiology*; D063766:Pediatric Obesity / Q000150:complications* / Q000453:epidemiology*; D017286:Polysomnography; D012307:Risk Factors; D020181:Sleep Apnea, Obstructive / Q000453:epidemiology* / Q000209:etiology*; D012894:Sleep Stages; D011795:Surveys and Questionnaires
keywords: Metabolic syndrome X; Obesity; Obstructive sleep apnea; Polysomnography; Sleep stages