title: Soluble urokinase-type plasminogen activator receptor is a novel biomarker predicting acute exacerbation in COPD.
abstract: BACKGROUND
  Chronic obstructive pulmonary disease (COPD) is a chronic inflammatory condition, and progresses with acute exacerbations. (AE). During AE, levels of acute phase reactants such as C-reactive protein (CRP) and inflammatory cells in the circulation increase. Soluble urokinase-type plasminogen activator receptor (suPAR) levels increase in acute viral and bacterial infections and in diseases involving chronic inflammation. The purpose of this study was to investigate the effectiveness of suPAR in predicting diagnosis of AE of COPD (AE-COPD) and response to treatment.
  
  
  METHODS
  The study population consisted of 43 patients diagnosed with AE-COPD and 30 healthy controls. suPAR, CRP, and fibrinogen levels were measured on the first day of hospitalization and on the seventh day of treatment.
  
  
  RESULTS
  We found that fibrinogen (P<0.001), CRP (P<0.001), and suPAR (P<0.001) were significantly higher in patients with AE-COPD than in healthy controls. Fibrinogen (P<0.001), CRP (P=0.001), and suPAR (P<0.001) were significantly decreased by the seventh day of treatment. However, the area under receiver operator characteristic curve showed that suPAR is superior to CRP and fibrinogen in distinguishing AE-COPD. There was a correlation between fibrinogen, CRP, and suPAR. However, only fibrinogen was a powerful predictor of suPAR in multiple linear regression. In multiple logistic regression, only suPAR and fibrinogen were strong predictors of AE-COPD (P=0.002 and P=0.014, respectively). Serum suPAR was negatively correlated with forced expiratory volume in 1 second (r=-478, P=0.001).
  
  
  CONCLUSIONS
  suPAR is a marker of acute inflammation. It is well correlated with such inflammation markers as CRP and fibrinogen. suPAR can be used as a predictor of AE-COPD and in monitoring response to treatment.
authors.affiliation: Department of Pulmonary Medicine, School of Medicine, Recep Tayyip Erdogan University, Rize, Turkey.
authors.forename: Aziz
authors.initials: A
authors.lastname: Gumus
authors.affiliation: Department of Pulmonary Medicine, School of Medicine, Namik Kemal University, Tekirdag, Turkey.
authors.forename: Nejat
authors.initials: N
authors.lastname: Altintas
authors.affiliation: Department of Pulmonary Medicine, School of Medicine, Recep Tayyip Erdogan University, Rize, Turkey.
authors.forename: Halit
authors.initials: H
authors.lastname: Cinarka
authors.affiliation: Department of Clinical Biochemistry, School of Medicine, Recep Tayyip Erdogan University, Rize, Turkey.
authors.forename: Aynur
authors.initials: A
authors.lastname: Kirbas
authors.affiliation: Department of Pulmonary Medicine, School of Medicine, Recep Tayyip Erdogan University, Rize, Turkey.
authors.forename: Muge
authors.initials: M
authors.lastname: Hazıroglu
authors.affiliation: Department of Pulmonary Medicine, School of Medicine, Recep Tayyip Erdogan University, Rize, Turkey.
authors.forename: Mevlut
authors.initials: M
authors.lastname: Karatas
authors.affiliation: Department of Pulmonary Medicine, School of Medicine, Recep Tayyip Erdogan University, Rize, Turkey.
authors.forename: Unal
authors.initials: U
authors.lastname: Sahin
mesh_terms: D000368:Aged; D019540:Area Under Curve; D015415:Biomarkers / Q000097:blood; D002097:C-Reactive Protein / Q000378:metabolism; D003430:Cross-Sectional Studies; D018450:Disease Progression; D016903:Drug Monitoring / Q000379:methods; D005260:Female; D005340:Fibrinogen / Q000378:metabolism; D006801:Humans; D018836:Inflammation Mediators / Q000097:blood*; D016014:Linear Models; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D011237:Predictive Value of Tests; D029424:Pulmonary Disease, Chronic Obstructive / Q000097:blood / Q000175:diagnosis* / Q000503:physiopathology / Q000628:therapy; D012372:ROC Curve; D055293:Receptors, Urokinase Plasminogen Activator / Q000097:blood*; D012189:Retrospective Studies; D013997:Time Factors; D016896:Treatment Outcome; D015854:Up-Regulation
chemical_list: D015415:Biomarkers; D018836:Inflammation Mediators; C524898:PLAUR protein, human; D055293:Receptors, Urokinase Plasminogen Activator; D005340:Fibrinogen; D002097:C-Reactive Protein
keywords: biomarker; chronic obstructive pulmonary disease; inflammation; suPAR