title: Effects of oxygen administration on the circulating vascular endothelial growth factor (VEGF) levels in patients with obstructive sleep apnea syndrome.
abstract: OBJECTIVE
  Repeated nocturnal hypoxia is implicated in the pathogenesis of cardiovascular complications in obstructive sleep apnea syndrome (OSAS). We hypothesized that circulating vascular endothelial growth factor (VEGF) levels are affected by nocturnal hypoxemia in patients with OSAS.
  
  
  METHODS
  We examined the serum VEGF levels in patients with OSAS and in control subjects. We also tested the effects of oxygen or air administration on the subjects' VEGF levels.
  
  
  METHODS
  Twenty-four OSAS patients (mean age 54.2 +/- 3.6 years) and 24 age-matched control subjects (53.2 +/- 3.6 years). Their serum samples were tested.
  
  
  RESULTS
  Serum VEGF levels at 8:00 AM were significantly higher in OSAS patients than in controls (p<0.01). VEGF levels decreased from 515 +/- 31 (pg/ml) to 178 +/- 16 (pg/m) (p<0.01) in OSAS patients whose nocturnal hypoxemia was found to be improved by administration of 2 l/min of oxygen during the night. However, the administration of compressed air affected neither the VEGF level nor nocturnal oxygen desaturation in OSAS patients.
  
  
  CONCLUSIONS
  These results indicate that circulating VEGF levels are elevated in OSAS patients, primarily due to nocturnal hypoxemia.
authors.affiliation: Department of Geriatric Medicine, The University of Tokyo Hospital, Tokyo.
authors.forename: Shinji
authors.initials: S
authors.lastname: Teramoto
authors.forename: Haruki
authors.initials: H
authors.lastname: Kume
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Yamamoto
authors.forename: Takeo
authors.initials: T
authors.lastname: Ishii
authors.forename: Akira
authors.initials: A
authors.lastname: Miyashita
authors.forename: Takeshi
authors.initials: T
authors.lastname: Matsuse
authors.forename: Masahiro
authors.initials: M
authors.lastname: Akishita
authors.forename: Kenji
authors.initials: K
authors.lastname: Toba
authors.forename: Yasuyoshi
authors.initials: Y
authors.lastname: Ouchi
mesh_terms: D000328:Adult; D000368:Aged; D002940:Circadian Rhythm; D005260:Female; D006801:Humans; D000860:Hypoxia / Q000097:blood / Q000209:etiology; D008297:Male; D010100:Oxygen / Q000494:pharmacology*; D020181:Sleep Apnea, Obstructive / Q000097:blood* / Q000150:complications; D042461:Vascular Endothelial Growth Factor A / Q000097:blood*
chemical_list: D042461:Vascular Endothelial Growth Factor A; D010100:Oxygen