title: Obstructive sleep apnea is independently associated with inflammation and insulin resistance, but not with blood pressure, plasma catecholamines, and endothelial function in obese subjects.
abstract: OBJECTIVE
  Obstructive sleep apnea (OSA) is associated with an increased risk of cardiovascular disease (CVD). Several of the proposed mechanisms for the development of CVD in OSA are similar to those proposed for the increased risk of CVD in obesity, so that it is difficult to determine the influence of OSA on these pathogenic mechanisms in obese individuals. The aim of this study was to evaluate the relationship of OSA with endothelial function, oxidative stress, inflammatory biomarkers, metabolic profile, sympathetic nervous system activity, and blood pressure (BP) in obese individuals.
  
  
  METHODS
  This cross-sectional study included 53 obese adults (28 women). Sleep study was performed with WatchPAT 200 (Itamar Medical, Caesarea, Israel) and the diagnosis of OSA was made when apnea-hypopnea index (AHI) ≥5 events/h (n = 33). All participants underwent evaluation of: body adiposity, BP, plasma catecholamines, high sensitivity C-reactive protein (hs-CRP), adiponectin, malondialdehyde, glucose, insulin, lipid profile, and endothelial function (EndoPAT 2000).
  
  
  RESULTS
  In univariate analysis, participants with OSA compared with those without OSA exhibited higher values of neck circumference, glucose, noradrenaline, and systolic BP. After adjustment for confounders, including adiposity, only glucose and hs-CRP were significantly higher in OSA patients. In correlation analysis, after controlling for confounders, AHI was positively and significantly associated with neck circumference and hs-CRP, while minimum O2 saturation was associated negatively and significantly with neck circumference, insulin and homeostatic model assessment-insulin resistance (HOMA-IR).
  
  
  CONCLUSIONS
  The present study suggests that in obese individuals OSA is independently associated with inflammation and insulin resistance, but not with BP, plasma catecholamines and endothelial function.
authors.affiliation: Discipline of Clinical and Experimental Pathophysiology, Rio de Janeiro State University, Rio de Janeiro, Rio de Janeiro, Brazil.
authors.forename: Luciene da Silva
authors.initials: Lda S
authors.lastname: Araújo
authors.affiliation: Discipline of Clinical and Experimental Pathophysiology, Rio de Janeiro State University, Rio de Janeiro, Rio de Janeiro, Brazil.
authors.forename: Julia Freitas Rodrigues
authors.initials: JF
authors.lastname: Fernandes
authors.affiliation: Department of Applied Nutrition, Nutrition Institute, Rio de Janeiro State University, Rio de Janeiro, Rio de Janeiro, Brazil. Electronic address: marciarsimas@gmail.com.
authors.forename: Márcia Regina Simas Torres
authors.initials: MR
authors.lastname: Klein
authors.affiliation: Discipline of Clinical and Experimental Pathophysiology, Rio de Janeiro State University, Rio de Janeiro, Rio de Janeiro, Brazil.
authors.forename: Antonio Felipe
authors.initials: AF
authors.lastname: Sanjuliani
mesh_terms: D000328:Adult; D001786:Blood Glucose / Q000378:metabolism; D001794:Blood Pressure; D002097:C-Reactive Protein / Q000378:metabolism; D002318:Cardiovascular Diseases / Q000097:blood / Q000150:complications; D002395:Catecholamines / Q000097:blood*; D003430:Cross-Sectional Studies; D004730:Endothelium, Vascular / Q000378:metabolism / Q000503:physiopathology; D005260:Female; D006801:Humans; D007249:Inflammation / Q000097:blood / Q000150:complications*; D007328:Insulin / Q000097:blood; D007333:Insulin Resistance; D007557:Israel; D008297:Male; D009765:Obesity / Q000097:blood / Q000150:complications*; D018384:Oxidative Stress; D020181:Sleep Apnea, Obstructive / Q000097:blood / Q000209:etiology*; D013564:Sympathetic Nervous System
chemical_list: D001786:Blood Glucose; D002395:Catecholamines; D007328:Insulin; D002097:C-Reactive Protein
keywords: Endothelial function; Inflammation; Insulin resistance; Obesity; Obstructive sleep apnea