title: Hypoxemia and glycemic control in type 2 diabetes mellitus with extreme obesity.
abstract: BACKGROUND
  Obstructive sleep apnea (OSA) has been shown to be associated with type 2 diabetes mellitus (DM). Studies on healthy individuals found that OSA is associated with lower insulin sensitivity. We hypothesized that nocturnal hypoxemia from OSA is associated with poorer glycemia in severely obese DM individuals.
  
  
  METHODS
  This was a retrospective observational study of 122 non-DM, 126 non-insulin-treated DM, and 35 insulin-treated DM patients. Data were collected on demographic characteristics, body mass index, and comorbidities. An overnight sleep study was performed in all patients, and OSA was defined as an apnea-hypopnea index of ≥5 events/h.
  
  
  RESULTS
  There were more males (P = .003) and a lower proportion of white Europeans (P = .010) among DM patients. The prevalence of OSA was 80.1% in DM and 63.1% in non-DM individuals (P = .001). DM individuals also had lower oxygen saturation (O2) (P = .0106), greater percentage of time spent under 90% oxygen saturation (%TST<90%) (P = .0067), and higher apnea-hypopnea index (P = .0085). Regression analysis showed that %TST<90% and minimum O2 saturations were associated with worse hemoglobin A1c results among DM individuals. Every 10% reduction in minimum O2 was associated with a 0.3% increase in HbA1c, whereas a 10% increase in %TST<90% was associated with a 0.2% increase in hemoglobin A1c after adjusting for a range of potential confounders.
  
  
  CONCLUSIONS
  The high OSA prevalence in DM individuals and a positive relationship between nocturnal hypoxemia and glycemia supports the need to assess correction of hypoxemia as a management strategy for glycemic control.
authors.affiliation: Specialist Weight Management Services (W.B.L., S.T.) and Academic Department of Sleep and Ventilation (D.B., M.N.), Heart of England National Health Service Foundation Trust, Birmingham, United Kingdom; Theme 8 (Diabetes) (W.B.L., S.T.), Birmingham and Black Country National Institute for Health Research Collaborations for Leadership in Applied Health Research and Care, University of Birmingham, Birmingham, B15, 2TT, United Kingdom; Thoracic and Sleep Medicine Department (D.B.), St Vincent's Hospital, Darlinghurst, Sydney, NSW 2010 Australia; National Health and Medical Research Council Centre for Integrated Research and Understanding Sleep (D.B,), Woolcock Institute of Medical Research, Glebe, Sydney, NSW 2037 Australia; Public Health, Epidemiology, and Biostatistics (P.A., G.N.T.), University of Birmingham, United Kingdom; Institute of Public Health (G.N.T.), Social and Preventive Medicine, Mannheim Medical Faculty, Heidelberg University, Mannheim, D-68167, Germany; Department of Medicine (S.T.), Weill Cornell Medical College New York, New York 10021, and Doha, 24144, Qatar; and Department of Medicine (S.T.), King's College London, London, SE5 9RJ, United Kingdom.
authors.forename: Wen Bun
authors.initials: WB
authors.lastname: Leong
authors.forename: Dev
authors.initials: D
authors.lastname: Banerjee
authors.forename: Melissa
authors.initials: M
authors.lastname: Nolen
authors.forename: Peymané
authors.initials: P
authors.lastname: Adab
authors.forename: G Neil
authors.initials: GN
authors.lastname: Thomas
authors.forename: Shahrad
authors.initials: S
authors.lastname: Taheri
mesh_terms: D000328:Adult; D015992:Body Mass Index; D002940:Circadian Rhythm / Q000502:physiology; D015897:Comorbidity; D015986:Confounding Factors, Epidemiologic; D003430:Cross-Sectional Studies; D003924:Diabetes Mellitus, Type 2 / Q000188:drug therapy / Q000453:epidemiology / Q000378:metabolism*; D005260:Female; D006442:Glycated Hemoglobin / Q000378:metabolism; D006801:Humans; D006943:Hyperglycemia / Q000188:drug therapy / Q000453:epidemiology / Q000378:metabolism*; D007004:Hypoglycemic Agents / Q000627:therapeutic use; D000860:Hypoxia / Q000453:epidemiology / Q000378:metabolism*; D007328:Insulin / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D009767:Obesity, Morbid / Q000453:epidemiology / Q000378:metabolism*; D015995:Prevalence; D012189:Retrospective Studies; D020181:Sleep Apnea, Obstructive / Q000453:epidemiology / Q000378:metabolism*
chemical_list: D006442:Glycated Hemoglobin; D007004:Hypoglycemic Agents; D007328:Insulin; C517652:hemoglobin A1c protein, human