title: Pulmonary hypertension in patients with obstructive sleep apnea syndrome.
abstract: BACKGROUND
  Obstructive sleep apnea syndrome (OSAS) is associated with an increased cardiovascular morbidity, including pulmonary hypertension. Little is known about factors influencing the degree of pulmonary hypertension and left ventricular dysfunction in patients with OSAS, especially in the absence of concomitant lung disease.
  
  
  METHODS
  Right heart catheterization, arterial blood gas analysis, and pulmonary function tests were performed in 92 consecutive patients (81 men and 11 women; mean +/- SD age, 53.1 +/- 11.0 years) with polysomnographically verified OSAS, in whom clinically significant lung disease was excluded.
  
  
  RESULTS
  Eighteen patients (20%) had mild pulmonary hypertension; 8 (44%) of them also had increased pulmonary capillary wedge pressures (Ppew). Left ventricular dysfunction was associated with arterial hypertension. Only Ppcw (r = 0.51; P < .001) and the percentage of time during sleep spent with an oxygen saturation below 90% (as an indicator of the severity of OSAS) (r = 0.34; P = .003) were significantly and independently associated with pulmonary artery pressure.
  
  
  CONCLUSIONS
  Obstructive sleep apnea syndrome can cause mild pulmonary hypertension, even in the absence of pulmonary disease. In these patients, pulmonary hypertension is of the postcapillary type, or-in patients with normal left ventricular function-strongly related to the severity of OSAS. Our findings indicate that OSAS may constitute an important, and independent, risk factor for pulmonary hypertension.
authors.affiliation: Department of Medicine I, Ruhr University Bochum, Marienhospital, Herne, Germany.
authors.forename: B M
authors.initials: BM
authors.lastname: Sanner
authors.forename: C
authors.initials: C
authors.lastname: Doberauer
authors.forename: M
authors.initials: M
authors.lastname: Konermann
authors.forename: A
authors.initials: A
authors.lastname: Sturm
authors.forename: W
authors.initials: W
authors.lastname: Zidek
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D006801:Humans; D006976:Hypertension, Pulmonary / Q000209:etiology* / Q000503:physiopathology; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D017286:Polysomnography; D012129:Respiratory Function Tests; D012307:Risk Factors; D012891:Sleep Apnea Syndromes / Q000150:complications* / Q000503:physiopathology