title: Serum Levels of Vascular Endothelial Growth Factor and Insulin-like Growth Factor Binding Protein-3 in Obstructive Sleep Apnea Patients: Effect of Continuous Positive Airway Pressure Treatment.
abstract: OBJECTIVE
  Hypoxia, a major feature of obstructive sleep apnea (OSA), modifies Vascular Endothelial Growth Factor (VEGF) and Insulin-like Growth Factor Binding Protein-3 (IGFBP-3) levels, which contribute to atherogenesis and occurrence of cardiovascular (CV) events. We assessed and compared serum levels of VEGF and IGFBP-3 in newly diagnosed OSA patients and controls, to explore associations with anthropometric and sleep parameters and to study the effect of continuous positive airway pressure (CPAP) treatment on these levels.
  
  
  METHODS
  Serum levels of VEGF and IGFBP-3 were measured in 65 OSA patients and 31 age- and body mass index- matched controls. In OSA patients, measurements were repeated after 6 months of CPAP therapy. All participants were non-smokers, without any comorbidities or systemic medication use.
  
  
  RESULTS
  At baseline, serum VEGF levels in OSA patients were higher compared with controls (p<0.001), while IGFBP-3 levels were lower (1.41±0.56 vs. 1.61±0.38 μg/ml, p=0.039). VEGF levels correlated with apnea-hypopnea index (r=0.336, p=0.001) and oxygen desaturation index (r=0.282, p=0.007). After 6 months on CPAP treatment, VEGF levels decreased in OSA patients (p<0.001), while IGFBP-3 levels increased (p<0.001).
  
  
  CONCLUSIONS
  In newly diagnosed OSA patients, serum levels of VEGF are elevated, while IGFBP-3 levels are low. After 6 months of CPAP treatment these levels change. These results may reflect an increased CV risk in untreated OSA patients, which is ameliorated after CPAP therapy.
authors.affiliation: Department of Pneumonology, Medical School, Democritus University of Thrace, Alexandroupolis, Greece.
authors.forename: Kostas
authors.initials: K
authors.lastname: Archontogeorgis
authors.affiliation: Laboratory of Hygiene and Environmental Protection, Medical School, Democritus University of Thrace, Alexandroupolis, Greece.
authors.forename: Evangelia
authors.initials: E
authors.lastname: Nena
authors.affiliation: Second Department of Internal Medicine, Medical School, Democritus University of Thrace, Alexandroupolis, Greece.
authors.forename: Nikolaos
authors.initials: N
authors.lastname: Papanas
authors.affiliation: Department of Pneumonology, Medical School, Democritus University of Thrace, Alexandroupolis, Greece.
authors.forename: Maria
authors.initials: M
authors.lastname: Xanthoudaki
authors.affiliation: Department of Pneumonology, General Hospital "G. Papanikolaou", Thessaloniki, Greece.
authors.forename: Olga
authors.initials: O
authors.lastname: Hatzizisi
authors.affiliation: Department of Pneumonology, General Hospital "G. Papanikolaou", Thessaloniki, Greece.
authors.forename: Georgios
authors.initials: G
authors.lastname: Kyriazis
authors.affiliation: Department of Pneumonology, General Hospital "G. Papanikolaou", Thessaloniki, Greece.
authors.forename: Venetia
authors.initials: V
authors.lastname: Tsara
authors.affiliation: Second Department of Internal Medicine, Medical School, Democritus University of Thrace, Alexandroupolis, Greece.
authors.forename: Efstratios
authors.initials: E
authors.lastname: Maltezos
authors.affiliation: Department of Pneumonology, Medical School, Democritus University of Thrace, Alexandroupolis, Greece.
authors.forename: Marios
authors.initials: M
authors.lastname: Froudarakis
authors.affiliation: Department of Pneumonology, Medical School, Democritus University of Thrace, Alexandroupolis, Greece.
authors.forename: Paschalis
authors.initials: P
authors.lastname: Steiropoulos
keywords: Continuous positive airway pressure; hypoxia; insulin-like growth factor binding protein-3; obstructive sleep apnea; treatment.; vascular endothelial growth factor