The Evidence of Hyperinflation on Chest X Ray and its Correlation with Air Flow Obstruction in COPD Patients

Introduction: According to the latest statistical and epidemiological studies, chronic obstructive pulmonary disease (COPD) will become the fourth leading cause of death in 2030 worldwide. Scientists are studying on methods to diagnose COPD in the patients in early stages, because it is a curable and preventable disease in early stages. In this study, evidences of hyperinflation on chest X- ray (CXR) of COPD patients were compared with pulmonary function test (PFT) finding. Materials and Methods: This cross-sectional study was done on 100 patients who were referred to the pulmonary clinic with symptoms of chronic cough and dyspnea. After taking history and performing physical examination, demographic information, history of smoking and bakery and frequency of exacerbations were recorded. Standard spirometry was performed and the severity of COPD was determined by GOLD (Global initiative for chronic Obstructive Lung Disease) staging. Additionally, they underwent CXR examination (PA and lateral). Collected data were analyzed in SPSS ver. 18. Results: In this study, there were 79 male and 21 female. The patients, 64% of whom were urban and 36% were rural dwellers. There was significant correlation between forced expiratory ??low (FEF) 50% predict with sterno-diaphragmatic angle and retro-sternal lucency (p=0.01, r=-0.26 and p=0.01, r=-0.25 respectively). Also there were significant correlations between the forced expiratory volume/forced vital capacity (FEV1/FVC) with retro-sternal lucency (p=0.006, r=-0.27) and FEV1%predict with sterno-diaphragmatic angle (p=0.002, r=-0.31). Conclusion: The study showed some evidences of lung hyperinflation on CXR which significantly associated with PFT parameters. Sternodiaphragmatic angle and retro-sternal lucency can be used to predict the severity of airway obstruction in patients with COPD, although the CXR finding cannot be substituted for PFT and CT data.