title: The role of obstructive sleep apnea in metabolic syndrome: a population-based study in women.
abstract: BACKGROUND
  The aim of this study was to assess associations between obstructive sleep apnea (OSA) and metabolic syndrome in a population-based sample of women.
  
  
  METHODS
  Four hundred women aged 20-70 years underwent a full-night polysomnography, fasting blood sampling and measurement of anthropometric variables. Metabolic syndrome was defined according to the National Cholesterol Education Program (NCEP) criteria.
  
  
  RESULTS
  The NCEP criteria of metabolic syndrome were fulfilled by 104 (26.0%) of the women. The frequency of metabolic syndrome increased from 10.5% in women with apnea-hypopnea-index (AHI) <5 to 57.1% in women with AHI ≥30 (p for trend <0.0001). In the multivariate analysis, the severity of OSA measured as AHI, ODI (oxygen desaturation index), minimal saturation or T(90) (percentage of time during night with saturation <90%) were associated with metabolic syndrome after adjustment for age, level of physical activity, smoking and alcohol consumption. AHI (adj. OR 1.45; 95% CI 1.11-1.91), ODI (1.37; 1.09-1.73) and minimal saturation level (0.93; 0.87-0.99) remained significantly associated with metabolic syndrome also when adjusting for the waist-to-hip-ratio. The three markers of OSA were independently associated with central obesity, hypertriglyceridemia and reduced HDL cholesterol concentration.
  
  
  CONCLUSIONS
  Measures of OSA were closely associated with metabolic syndrome and its components in this population-based sample of women also after adjustments. Therefore, when the health consequences of sleep-disordered breathing are investigated it is important to consider metabolic syndrome. Sleep-disordered breathing should also be considered when treating patients with metabolic syndrome.
authors.affiliation: Department of Medical Sciences, Respiratory Medicine and Allergology, Uppsala University, Sweden.
authors.forename: Jenny
authors.initials: J
authors.lastname: Theorell-Haglöw
authors.forename: Christian
authors.initials: C
authors.lastname: Berne
authors.forename: Christer
authors.initials: C
authors.lastname: Janson
authors.forename: Eva
authors.initials: E
authors.lastname: Lindberg
mesh_terms: D000328:Adult; D017677:Age Distribution; D000368:Aged; D015992:Body Mass Index; D015897:Comorbidity; D005260:Female; D006801:Humans; D024821:Metabolic Syndrome / Q000453:epidemiology*; D008875:Middle Aged; D015999:Multivariate Analysis; D017286:Polysomnography; D015995:Prevalence; D020181:Sleep Apnea, Obstructive / Q000175:diagnosis* / Q000453:epidemiology*; D055815:Young Adult