AUTHOR=Tung Nguyen Thanh , Ho Shu-Chuan , Lu Yueh-Hsun , Chen Tzu-Tao , Lee Kang-Yun , Chen Kuan-Yuan , Wu Chih-Da , Chung Kian Fan , Kuo Han-Pin , Thao Huynh Nguyen Xuan , Dung Hoang Ba , Thuy Tran Phan Chung , Wu Sheng-Ming , Kou Hsiao-Yun , Lee Yueh-Lun , Chuang Hsiao-Chi 

TITLE=Association Between Air Pollution and Lung Lobar Emphysema in COPD

JOURNAL=Frontiers in Medicine

VOLUME=Volume 8 - 2021

YEAR=2021

URL=https://www.frontiersin.org/journals/medicine/articles/10.3389/fmed.2021.705792

DOI=10.3389/fmed.2021.705792

ISSN=2296-858X

ABSTRACT=The development of emphysema has been linked to air pollution; however, the association of air pollution with the extent of lobar emphysema remains unclear. This study examined the association of PM2.5 (≤ 2.5 μm), NO2, and O3 level of exposure with the presence of emphysema in 86 chronic obstructive pulmonary disease (COPD) patients. Exposure to the air pollution estimated using the land-use regression model was associated with lung function, BODE (a body-mass index, degree of obstruction, dyspnea severity, and exercise capacity index) quartiles and emphysema measured as low-attenuation areas on high resolution computed tomography (HR-CT) lung scans. Using paraseptal emphysema as the reference group, we observed that 1-ppb increase in O3 was associated with 1.798-fold increased crude odds ratio of panlobular emphysema (p<0.05). We observed that PM2.5 was associated with BODE quartiles, mMRC dyspnea score, and exercise capacity (all p<0.05).  We found that PM2.5, NO2, and O3 was associated with an increased degree of upper lobe emphysema and lower lobe emphysema (all p<0.05). Furthermore, we observed that an increase in PM2.5, NO2, and O3 was associated with greater increases in upper lobe emphysema than in lower lobe emphysema. In conclusion, exposure to O3 can be associated with higher risk of panlobular emphysema than paraseptal emphysema in COPD patients. Emphysema severity in lung lobes, especially the upper lobes, may be linked to air pollution exposure in COPD.