title: Type 2 diabetes and pre-diabetes are associated with obstructive sleep apnea in extremely obese subjects: a cross-sectional study.
abstract: BACKGROUND
  Obstructive sleep apnea (OSA) is a common yet underdiagnosed condition. The aim of our study is to test whether prediabetes and type 2 diabetes are associated with obstructive sleep apnea (OSA) in extremely obese (BMI ≥ 40 kg/m²) subjects.
  
  
  METHODS
  One hundred and thirty seven consecutive extremely obese patients (99 females) from a controlled clinical trial [MOBIL-study (Morbid Obesity treatment, Bariatric surgery versus Intensive Lifestyle intervention Study) (ClinicalTrials.gov number NCT00273104)] underwent somnography with Embletta® and a 2-hour oral glucose tolerance test (OGTT). OSA was defined by an apnea-hypopnea index (AHI) ≥ 5 events/hour. Patients were categorized into three groups according to criteria from the American Diabetes Association: normal glucose tolerance, pre-diabetes and type 2 diabetes. Multiple logistic regression analysis was used to identify possible determinants of OSA.
  
  
  RESULTS
  The patients had a mean (SD) age of 43 (11) years and a body mass index (BMI) of 46.9 (5.7) kg/m². Males had significantly higher AHI than females, 29 (25) vs 12 (17) events/hour, p < 0.001. OSA was observed in 81% of men and in 55% of women, p = 0.008. Twenty-nine percent of subjects had normal glucose tolerance, 42% had pre-diabetes and 29% had type 2 diabetes. Among the patients with normal glucose tolerance 33% had OSA, while 67% of the pre-diabetic patients and 78% of the type 2 diabetic patients had OSA, p < 0.001. After adjusting for age, gender, BMI, high sensitive CRP and HOMA-IR, both pre-diabetes and type 2 diabetes were still associated with OSA, odds ratios 3.18 (95% CI 1.00, 10.07), p = 0.049 and 4.17 (1.09, 15.88), p = 0.036, respectively. Mean serum leptin was significantly lower in the OSA than in the non-OSA group, while other measures of inflammation did not differ significantly between groups.
  
  
  CONCLUSIONS
  Type 2 diabetes and pre-diabetes are associated with OSA in extremely obese subjects.
  
  
  BACKGROUND
  MOBIL-study (Morbid Obesity treatment, Bariatric surgery versus Intensive Lifestyle intervention Study) (ClinicalTrials.gov number NCT00273104).
authors.affiliation: Morbid Obesity Centre, Department of Medicine, Vestfold Hospital Trust, 3103 Tønsberg, Norway. janmagnus.fredheim@siv.no
authors.forename: Jan Magnus
authors.initials: JM
authors.lastname: Fredheim
authors.forename: Jan
authors.initials: J
authors.lastname: Rollheim
authors.forename: Torbjørn
authors.initials: T
authors.lastname: Omland
authors.forename: Dag
authors.initials: D
authors.lastname: Hofsø
authors.forename: Jo
authors.initials: J
authors.lastname: Røislien
authors.forename: Kristian
authors.initials: K
authors.lastname: Vegsgaard
authors.forename: Jøran
authors.initials: J
authors.lastname: Hjelmesæth
mesh_terms: D000328:Adult; D003430:Cross-Sectional Studies; D003924:Diabetes Mellitus, Type 2 / Q000453:epidemiology* / Q000378:metabolism / Q000503:physiopathology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000453:epidemiology* / Q000378:metabolism / Q000503:physiopathology; D009767:Obesity, Morbid / Q000453:epidemiology / Q000378:metabolism / Q000503:physiopathology; D011236:Prediabetic State / Q000453:epidemiology* / Q000378:metabolism / Q000503:physiopathology; D020181:Sleep Apnea, Obstructive / Q000453:epidemiology* / Q000378:metabolism / Q000503:physiopathology