title: Obstructive sleep apnoea and diabetes: an update.
abstract: OBJECTIVE
  The relationship between obstructive sleep apnoea (OSA) and dysglycaemia is well established. However, uncertainty remains as to the extent that obesity mediates this relationship. The impact of OSA treatment on glucose metabolism and the consequences of having OSA in patients with diabetes is unclear. This review aims to summarize the latest evidence regarding the links between OSA and dysglycaemia.
  
  
  RESULTS
  OSA is associated with insulin resistance in lean individuals and predicts insulin resistance worsening longitudinally. Continuous positive airway pressure (CPAP) lowers insulin resistance in CPAP-compliant patients. OSA is associated with impaired β-cell function. In patients with type 2 diabetes (T2D), the association between OSA and glycosylated haemoglobin (HbA1c) is related to nocturnal hypoxaemia. Apnoea hypopnoea index (AHI) during rapid eye movement (REM) (not non-REM) sleep is associated with HbA1c. In-laboratory, supervised CPAP improves glycaemia. OSA is associated with and predicts the progression of some diabetic vascular complications. Intensive lifestyle intervention in patients with T2D improves OSA independent of weight loss.
  
  
  CONCLUSIONS
  OSA is associated with insulin resistance and β-cell dysfunction independent of obesity. OSA is associated with HbA1c and vascular complications in patients with T2D. CPAP might improve insulin resistance and glycaemic measures. Lifestyle intervention has a significant impact on AHI in patients with T2D.
authors.affiliation: aCentre of Endocrinology, Diabetes and Metabolism, University of Birmingham bDepartment of Diabetes and Endocrinology, Heart of England NHS Foundation Trust, Birmingham cDepartment of Respiratory Medicine, University Hospital of Coventry and Warwickshire, Coventry, West Midlands, UK.
authors.forename: Abd A
authors.initials: AA
authors.lastname: Tahrani
authors.forename: Asad
authors.initials: A
authors.lastname: Ali
authors.forename: Martin J
authors.initials: MJ
authors.lastname: Stevens
mesh_terms: D001786:Blood Glucose / Q000378:metabolism; D045422:Continuous Positive Airway Pressure; D048909:Diabetes Complications / Q000097:blood / Q000188:drug therapy / Q000503:physiopathology*; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000150:complications / Q000188:drug therapy / Q000503:physiopathology*; D005260:Female; D006442:Glycated Hemoglobin / Q000378:metabolism; D006801:Humans; D007333:Insulin Resistance; D008297:Male; D009765:Obesity / Q000097:blood; D011379:Prognosis; D012307:Risk Factors; D040242:Risk Reduction Behavior; D020181:Sleep Apnea, Obstructive / Q000097:blood / Q000150:complications / Q000503:physiopathology* / Q000628:therapy; D012895:Sleep, REM; D016896:Treatment Outcome
chemical_list: D001786:Blood Glucose; D006442:Glycated Hemoglobin; C517652:hemoglobin A1c protein, human