title: Analysis of vascular endothelial growth factor levels in induced sputum samples from patients with cough variant asthma.
abstract: BACKGROUND
  We previously found that vascular endothelial growth factor (VEGF) levels in induced sputum samples are increased in patients with classic asthma and are associated with the degree of airflow obstruction and airway microvascular permeability.
  
  
  OBJECTIVE
  To examine VEGF levels and the degree of airway microvascular permeability in patients with cough variant asthma (CVA).
  
  
  METHODS
  Levels of VEGF in induced sputum samples and airway microvascular permeability were examined in 12 controls, 16 patients with CVA, and 16 patients with classic asthma. We also evaluated the relationship between VEGF level and the clinical features of these 2 disorders.
  
  
  RESULTS
  Mean (SD) VEGF levels and airway vascular permeability index values were significantly higher in patients with CVA (VEGF: 2,520 [1,050] pg/mL; P < .001; vascular permeability index: 0.017 [0.006]; P = .003) and classic asthma (4,750 [1,260] pg/mL; P < .001; 0.028 [0.009]; P < .001) than in controls (1,420 [1,230] pg/mL; 0.009 [0.003]). Furthermore, these values were significantly higher in patients with classic asthma vs CVA. We also found significant correlations between VEGF level and airway vascular permeability index in patients with CVA (r = 0.60; P = .02) vs classic asthma (r = 0.83; P = .001). Furthermore, VEGF levels were inversely correlated with the degree of airflow obstruction and airway hyperresponsiveness to methacholine in patients with CVA and classic asthma.
  
  
  CONCLUSIONS
  Airway microvascular hyperpermeability induced by elevated VEGF levels contributes to abnormal airway function in CVA and classic asthma, and differences in the clinical features of these 2 disorders may depend on airway VEGF levels.
authors.affiliation: Department of Respiratory Medicine, Graduate School of Medicine, Osaka City University, Osaka, Japan. kanazawa-h@med.osaka-cu.ac.jp
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Kanazawa
authors.forename: Yohsuke
authors.initials: Y
authors.lastname: Eguchi
authors.forename: Naho
authors.initials: N
authors.lastname: Nomura
authors.forename: Junichi
authors.initials: J
authors.lastname: Yoshikawa
mesh_terms: D000328:Adult; D001249:Asthma / Q000276:immunology / Q000378:metabolism* / Q000503:physiopathology; D002199:Capillary Permeability / Q000276:immunology; D003371:Cough / Q000276:immunology / Q000378:metabolism* / Q000503:physiopathology; D047150:Eosinophil Cationic Protein / Q000097:blood; D004804:Eosinophils / Q000276:immunology; D005260:Female; D006801:Humans; D008168:Lung / Q000098:blood supply; D008297:Male; D009569:Nitric Oxide / Q000032:analysis; D012129:Respiratory Function Tests; D013183:Sputum / Q000378:metabolism*; D042461:Vascular Endothelial Growth Factor A / Q000032:analysis*
chemical_list: D042461:Vascular Endothelial Growth Factor A; D009569:Nitric Oxide; D047150:Eosinophil Cationic Protein