Evaluation of upper airway involvement and interleukin-8 levels in nasal lavage fluid of stable COPD patients

Object: Sinonasal (upper respiratory) involvement in COPD has traditionally been a less frequented topic. IL-8 has been used to quantify the extent of airway inflammation. The aim of this study was to demonstrate the presence of upper airway involvement in COPD in patients with nasal symptoms by measuring IL-8 levels in nasal lavage material, while attempting to establish a possible link of such involvement with severity of disease. Method: Forty-seven patients with different stages (I-IV) of COPD, as determined by GOLD criteria, along with 23 healthy controls were enrolled in this study. All patients underwent pulmonary function testing, and values for FEV1, FVC, FEV1/FVC,and medical history were recorded. Patients were also asked to fill out a “sinonasal outcome test” (SNOT-20) quality of life questionnaire. This was followed by rhinoscopic evaluation be upper airway. IL-8 levels in nasal lavage material were measured using ELISA method. Results: Although the median IL-8 level of patients with stable COPD was higher than that for healthy controls, but the difference was insignificant (p=0.117). A longer history of cigarette smoking was correlated with a higher level of nasal IL-8 (p=0.042). IL-8 levels increased with disease stage (p=0.044). Patients with COPD had significantly higher SNOT-20 scores when compared with healthy controls (p=0.001). Our study results may support the “unified airway hypothesis” for COPD patients. The goal of treating sinonasal disease is to decrease the frequency of exacerbations while at the same time improving quality of life.