title: Eight Hours of Nightly Continuous Positive Airway Pressure Treatment of Obstructive Sleep Apnea Improves Glucose Metabolism in Patients with Prediabetes. A Randomized Controlled Trial.
abstract: BACKGROUND
  Although obstructive sleep apnea (OSA) is associated with impaired glucose tolerance and diabetes, it remains unclear whether OSA treatment with continuous positive airway pressure (CPAP) has metabolic benefits.
  
  
  OBJECTIVE
  To determine the effect of 8-hour nightly CPAP treatment on glucose metabolism in individuals with prediabetes and OSA.
  
  
  METHODS
  In a randomized controlled parallel group study, 39 participants were randomly assigned to receive either 8-hour nightly CPAP (n = 26) or oral placebo (n = 13). Sleep was polysomnographically recorded in the laboratory on each night. CPAP adherence was ensured by continuous supervision. Participants continued their daily routine activities outside the laboratory. Glucose metabolism was assessed at baseline and after 2 weeks of assigned treatment using both the oral and intravenous glucose tolerance tests. The primary outcome was the overall glucose response as quantified by the area under the curve for glucose during 2-hour oral glucose tolerance testing. Secondary outcomes included fasting and 2-hour glucose and insulin, the area under the curves for insulin and insulin secretion, norepinephrine, insulin sensitivity, acute insulin response to glucose, and 24-hour blood pressure.
  
  
  RESULTS
  The overall glucose response was reduced (treatment difference: -1,276.9 [mg/dl] · min [95% confidence interval, -2,392.4 to -161.5]; P = 0.03) and insulin sensitivity was improved (treatment difference: 0.77 [mU/L](-1) · min(-1) [95% confidence interval, 0.03-1.52]; P = 0.04) with CPAP as compared with placebo. Additionally, norepinephrine levels and 24-hour blood pressure were reduced with CPAP as compared with placebo.
  
  
  CONCLUSIONS
  In patients with prediabetes, 8-hour nightly CPAP treatment for 2 weeks improves glucose metabolism compared with placebo. Thus, CPAP treatment may be beneficial for metabolic risk reduction. Clinical trial registered with www.clinicaltrials.gov (NCT 01156116).
authors.affiliation: 1 Respiratory Division, Department of Medicine, McGill University, Montreal, Quebec, Canada; and.
authors.forename: Sushmita
authors.initials: S
authors.lastname: Pamidi
authors.affiliation: 2 Department of Public Health Sciences and.
authors.forename: Kristen
authors.initials: K
authors.lastname: Wroblewski
authors.affiliation: 3 Department of Medicine, University of Chicago, Chicago, Illinois.
authors.forename: Magdalena
authors.initials: M
authors.lastname: Stepien
authors.affiliation: 3 Department of Medicine, University of Chicago, Chicago, Illinois.
authors.forename: Khalid
authors.initials: K
authors.lastname: Sharif-Sidi
authors.affiliation: 3 Department of Medicine, University of Chicago, Chicago, Illinois.
authors.forename: Jennifer
authors.initials: J
authors.lastname: Kilkus
authors.affiliation: 3 Department of Medicine, University of Chicago, Chicago, Illinois.
authors.forename: Harry
authors.initials: H
authors.lastname: Whitmore
authors.affiliation: 3 Department of Medicine, University of Chicago, Chicago, Illinois.
authors.forename: Esra
authors.initials: E
authors.lastname: Tasali
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers / Q000097:blood; D001786:Blood Glucose / Q000378:metabolism*; D045422:Continuous Positive Airway Pressure; D005260:Female; D006801:Humans; D007333:Insulin Resistance; D008297:Male; D008875:Middle Aged; D017286:Polysomnography; D011236:Prediabetic State / Q000097:blood* / Q000150:complications; D012372:ROC Curve; D020181:Sleep Apnea, Obstructive / Q000150:complications / Q000628:therapy*; D016896:Treatment Outcome
chemical_list: D015415:Biomarkers; D001786:Blood Glucose
keywords: CPAP; glucose; metabolic; norepinephrine; obstructive sleep apnea