title: Impact of obstructive sleep apnea on insulin resistance and glucose tolerance in women with polycystic ovary syndrome.
abstract: BACKGROUND
  Insulin resistance, impaired glucose tolerance, and type 2 diabetes are common in women with polycystic ovary syndrome (PCOS). Obstructive sleep apnea (OSA) has been linked to metabolic dysfunction. We studied women with and without PCOS to determine the extent to which OSA is responsible for insulin resistance and glucose intolerance in PCOS.
  
  
  METHODS
  In a prospective design, 52 women with PCOS and 21 women without PCOS of similar age and body mass index had an overnight polysomnogram and a 75-g oral glucose tolerance test.
  
  
  RESULTS
  Twenty-nine women (56%) with PCOS had OSA compared with four controls (19%) (adjusted odds ratio 7.1; 95% confidence interval, 1.7-45.7; P = 0.01). PCOS women with OSA were more insulin resistant than those without OSA [homeostasis model assessment (HOMA) index 5.7 +/- 0.4 vs. 3.5 +/- 0.4; P = 0.006] after controlling for age, body mass index, and ethnicity. Impaired glucose tolerance was found in 16 of 29 (55%) PCOS women with OSA and only six of 23 (26%) of those without OSA (unadjusted P = 0.049). Insulin resistance and glucose intolerance were highly correlated with the presence and severity of OSA. Among PCOS women with normal glucose tolerance, the presence of OSA was associated with a nearly 2-fold higher fasting insulin level and HOMA index. The severity of OSA was a highly significant predictor of the fasting concentrations of glucose and insulin as well as the 2-h glucose concentration and HOMA index.
  
  
  CONCLUSIONS
  OSA is a highly prevalent and important determinant of insulin resistance, glucose intolerance, and type 2 diabetes in PCOS.
authors.affiliation: Department of Medicine, University of Chicago, Chicago, Illinois 60637, USA.
authors.forename: Esra
authors.initials: E
authors.lastname: Tasali
authors.forename: Eve
authors.initials: E
authors.lastname: Van Cauter
authors.forename: Leslie
authors.initials: L
authors.lastname: Hoffman
authors.forename: David A
authors.initials: DA
authors.lastname: Ehrmann
mesh_terms: D000328:Adult; D001143:Arousal / Q000502:physiology; D016022:Case-Control Studies; D005260:Female; D018149:Glucose Intolerance / Q000097:blood / Q000150:complications* / Q000378:metabolism; D005951:Glucose Tolerance Test; D006801:Humans; D007333:Insulin Resistance / Q000502:physiology*; D011085:Polycystic Ovary Syndrome / Q000097:blood / Q000150:complications* / Q000378:metabolism; D017286:Polysomnography; D011446:Prospective Studies; D020181:Sleep Apnea, Obstructive / Q000097:blood / Q000150:complications* / Q000378:metabolism