title: Vascular endothelial growth factor levels in induced sputum and emphysematous changes in smoking asthmatic patients.
abstract: BACKGROUND
  Although asthmatic patients frequently smoke cigarettes, the effect of smoking on asthmatic lungs has not been extensively studied. Vascular endothelial growth factor (VEGF) has been suggested to play a role in the pathogenesis of asthma and emphysema.
  
  
  OBJECTIVE
  To determine whether the level of airway VEGF might be related to emphysematous lung changes in asthmatic patients with a history of smoking.
  
  
  METHODS
  Pulmonary function tests and volumetric computed tomography (CT) of the lungs were performed in 10 ex-smoking and 15 nonsmoking asthmatic patients. Levels of VEGF were evaluated in the supernatants of induced sputum using an enzyme-linked immunosorbent assay method in these 25 asthmatic patients and in 10 healthy nonsmoking controls. Associations among sputum VEGF levels, emphysema indices on CT, and clinical variables were analyzed.
  
  
  RESULTS
  Ex-smoking asthmatic patients showed a higher emphysema index on volumetric CT and a decreased mean forced expiratory volume in 1 second to forced vital capacity ratio compared with nonsmoking asthmatic patients. Sputum VEGF levels in asthmatic patients with a history of smoking were significantly lower than those in nonsmoking asthmatic patients but remained higher than those in control subjects. Furthermore, the emphysema index was significantly correlated with sputum VEGF levels in asthmatic patients.
  
  
  CONCLUSIONS
  Lower VEGF levels in the airway might bea surrogate marker for emphysematous changes in the lungs, especially in asthmatic patients with a history of smoking.
authors: Division of Allergy and Clinical Immunology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
authors: Yun-Jeong
authors: YJ
authors: Bae
authors: Tae-Bum
authors: TB
authors: Kim
authors: Keun Ai
authors: KA
authors: Moon
authors: Ki-Young
authors: KY
authors: Lee
authors: Chan Sun
authors: CS
authors: Park
authors: Joon Beom
authors: JB
authors: Seo
authors: Eun Jin
authors: EJ
authors: Chae
authors: Hee-Bom
authors: HB
authors: Moon
authors: You Sook
authors: YS
authors: Cho
mesh_terms: D000328:Adult; D000368:Aged; D001249:Asthma / Q000378:metabolism* / Q000503:physiopathology; D015415:Biomarkers / Q000378:metabolism; D054893:Cone-Beam Computed Tomography; D005260:Female; D005541:Forced Expiratory Volume / Q000502:physiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D009504:Neutrophils / Q000473:pathology; D011656:Pulmonary Emphysema / Q000378:metabolism / Q000473:pathology*; D012907:Smoking / Q000378:metabolism* / Q000503:physiopathology; D013183:Sputum / Q000166:cytology / Q000378:metabolism*; D042461:Vascular Endothelial Growth Factor A / Q000378:metabolism*; D014797:Vital Capacity / Q000502:physiology
chemical_list: D015415:Biomarkers; C467484:VEGFA protein, human; D042461:Vascular Endothelial Growth Factor A