Contributors of the Severity of Airflow Limitation in COPD Patients. |
Yoonki Hong, Eun Jin Chae, Joon Beom Seo, Ji Hyun Lee, Eun Kyung Kim, Young Kyung Lee, Tae Hyung Kim, Woo Jin Kim, Jin Hwa Lee, Sang Min Lee, Sangyeub Lee, Seong Yong Lim, Tae Rim Shin, Ho Il Yoon, Seung Soo Sheen, Seung Won Ra, Jae Seung Lee, Jin Won Huh, Sang Do Lee, Yeon Mok Oh |
1Department of Pulmonary and Critical Care Medicine and Clinical Research Center for Chronic Obstructive Airway Diseases, Seoul, Korea. ymoh55@amc.seoul.kr 2Department of Radiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea. 3Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Bundang CHA Hospital, CHA University College of Medicine, Seongnam, Korea. 4Department of Radiology, East-West Neo Medical Center, Kyunghee University School of Medicine, Seoul, Korea. 5Division of Pulmonology, Department of Internal Medicine, Hanyang University Guri Hospital, Hanyang University College of Medicine, Guri, Korea. 6Department of Internal Medicine, College of Medicine, Kangwon National University, Chuncheon, Korea. 7Department of Internal Medicine, Ewha Womans University Mokdong Hospital, Ewha Womans University College of Medicine, Seoul, Korea. 8Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea. 9Division of Respiratory and Critical Care Medicine, Department of Internal Medicine, Korea University Anam Hospital, Korea University College of Medicine, Seoul, Korea. 10Division of Pulmonary and Critical Care Medicine, Department of Medicine, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul, Korea. 11Department of Internal Medicine, Kangnam Sacred Heart Hospital, Hallym University College of Medicine, Seoul, Korea. 12Department of Internal Medicine, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam, Korea. 13Department of Pulmonary and Critical Care Medicine, Ajou University School of Medicine, Suwon, Korea. 14Department of Internal Medicine, Ulsan University Hospital, University of Ulsan College of Medicine, Ulsan, Korea. |
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Abstract |
BACKGROUND Although airway obstruction in chronic obstructive pulmonary disease (COPD) is due to pathologic processes in both the airways and the lung parenchyma, the contribution of these processes, as well as other factors, have not yet been evaluated quantitatively. We therefore quantitatively evaluated the factors contributing to airflow limitation in patients with COPD. METHODS: The 213 COPD patients were aged >45 years, had smoked >10 pack-years of cigarettes, and had a post-bronchodilator forced expiratory volume in one second (FEV1)/forced vital capacity (FVC) <0.7. All patients were evaluated by medical interviews, physical examination, spirometry, bronchodilator reversibility tests, lung volume, and 6-minute walk tests. In addition, volumetric computed tomography (CT) was performed to evaluate airway wall thickness, emphysema severity, and mean lung density ratio at full expiration and inspiration. Multiple linear regression analysis was performed to identify the variables independently associated with FEV1 - the index of the severity of airflow limitation. RESULTS: Multiple linear regression analysis showed that CT measurements of mean lung density ratio (standardized coefficient beta=-0.46; p<0.001), emphysema severity (volume fraction of the lung less than -950 HU at full inspiration; beta=-0.24; p<0.001), and airway wall thickness (mean wall area %; beta=-0.19, p=0.001), as well as current smoking status (beta=-0.14; p=0.009) were independent contributors to FEV1. CONCLUSION: Mean lung density ratio, emphysema severity, and airway wall thickness evaluated by volumetric CT and smoking status could independently contribute to the severity of airflow limitation in patients with COPD. |
Key Words:
Pulmonary Disease, Chronic Obstructive, Forced Expiratory Volumes, Tomography, X-Ray Computed |
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