Soluble urokinase-type plasminogen activator receptor is a novel biomarker predicting acute exacerbation in COPD

Abstract

<b>Background:</b> Chronic obstructive pulmonary disease (COPD) is a chronic inflammatory condition proceeding with acute exacerbations (AE). 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-COPD and response to treatment. <b>Methods:</b> The study population consisted of 43 patients diagnosed with AE-COPD and a 30-healthy control. suPAR, C-RP, fibrinogen levels were measured on the first day of hospitalisation and on the seventh day of treatment. <b>Results:</b> We found that fibrinogen (p&lt;0.001), CRP (p&lt;0.001) and suPAR (p&lt;0.001) were significantly higher in patients with AE-COPD than in healthy controls. Fibrinogen (p&lt;0.001), CRP (p=0.001) and suPAR (p&lt;0.001) were significantly decreased by seven-day of treatment. However the area under receiver operator characteristic (ROC) 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 powerful predictor of suPAR in multiple linear regression. In multiple logistic regression, only suPAR and fibrinogen were a strong predictor of AE-COPD (p = 0.002) (p=0.014) respectively. Serum suPAR was negatively correlated with FEV1(r = - 478, p=0.001). <b>Conclusion:</b> 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.