title: The severity of oxygen desaturation is predictive of carotid wall thickening and plaque occurrence.
abstract: OBJECTIVE
  To characterize carotid intima-media thickness (IMT) and plaque occurrence in patients with newly diagnosed obstructive sleep apnea (OSA) without known cardiovascular disease.
  
  
  METHODS
  Prospective study.
  
  
  METHODS
  Sleep Laboratory and Department of Cardiology of Grenoble University Hospital.
  
  
  METHODS
  OSA syndrome is associated with an increased cardiovascular risk. Carotid IMT is recognized as a marker of preclinic atheroma. A small number of studies have analyzed large-artery wall modifications in OSA syndrome. Eighty-three patients (74 men; mean age +/- SD, 48 +/- 11 years; mean body mass index, 27.4 +/- 4.2 kg/m(2)) were included. Mean respiratory disturbance index was 40.7 +/- 19.2/h, mean nocturnal arterial oxygen saturation (Sao(2)) was 93.1 +/- 2.0%, and mean percentage of recording time spent at Sao(2) < 90% was 8.6 +/- 16.8%. Clinical BP was measured following European Society of Hypertension/European Society of Cardiology recommendations, and 24-h ambulatory BP monitoring was assessed. Ultrasonography was used to determine the carotid IMT and atheromatous plaque occurrence.
  
  
  RESULTS
  Twenty-five of 83 patients (30%) had carotid wall hypertrophy (IMT > 0.8 mm). In a logistic regression model, mean nocturnal Sao(2) < 92% (odds ratio [OR], 3.9; 95% confidence interval [CI], 1.1 to 12.7) was associated with carotid wall hypertrophy. ORs were even higher after adjustment for BP status (OR, 10.6; 95% CI, 1.6 to 50.9 in normotensive patients) and glucose levels (OR, 4.5; 95% CI, 1.0 to 20.9). Mean nocturnal Sao(2) < 92% and minimal nocturnal Sao(2) < 80% (ORs, 3.1 and 3.1; 95% CIs, 1.0 to 9.4 and 1.0 to 8.5, respectively) were associated with the presence of carotid plaque formation independently of the BP status (hypertensive or normotensive).
  
  
  CONCLUSIONS
  The severity of oxygen desaturation appears to be one of the best predictors for carotid IMT and plaque occurrence in OSA patients without known cardiovascular disease. Thus, carotid IMT and plaque formation appeared as early cardiovascular consequences in OSA patients.
authors.affiliation: Department of Cardiology and Hypertension, University Hospital, EFCR University Hospital, Grenoble, France. JPBaguet@chu-grenoble.fr
authors.forename: Jean-Philippe
authors.initials: JP
authors.lastname: Baguet
authors.forename: Laure
authors.initials: L
authors.lastname: Hammer
authors.forename: Patrick
authors.initials: P
authors.lastname: Lévy
authors.forename: Hélène
authors.initials: H
authors.lastname: Pierre
authors.forename: Sandrine
authors.initials: S
authors.lastname: Launois
authors.forename: Jean-Michel
authors.initials: JM
authors.lastname: Mallion
authors.forename: Jean-Louis
authors.initials: JL
authors.lastname: Pépin
mesh_terms: D000328:Adult; D000368:Aged; D001794:Blood Pressure; D002340:Carotid Artery Diseases / Q000473:pathology; D002343:Carotid Artery, Internal / Q000000981:diagnostic imaging / Q000473:pathology*; D045422:Continuous Positive Airway Pressure; D005260:Female; D006339:Heart Rate; D006801:Humans; D006984:Hypertrophy; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D010100:Oxygen / Q000097:blood*; D017286:Polysomnography; D020181:Sleep Apnea, Obstructive / Q000473:pathology* / Q000503:physiopathology; D017539:Tunica Intima / Q000473:pathology*; D017540:Tunica Media / Q000473:pathology*; D014463:Ultrasonography
chemical_list: D010100:Oxygen