Abstract:
BACKGROUND:The relative roles of mucus plugs and emphysema in mechanisms of airflow limitation and hypoxemia in smokers with chronic obstructive pulmonary disease (COPD) are uncertain. METHODS:We analyzed computed tomography (CT) lung images and lung function in participants in the Subpopulations and Intermediate Outcome Measures in COPD Study. Radiologists scored mucus plugs on CT lung images and imaging software automatically quantified percent emphysema. Unadjusted and adjusted relationships between mucus plug score, percent emphysema, and lung function were determined using regression. RESULTS:Among 400 smokers, 229 (57%) had mucus plugs and 207 (52%) had emphysema and subgroups could be identified with mucus dominant and emphysema dominant disease. Only 33% of smokers with high mucus plug scores had mucus symptoms. Mucus plug score and percent emphysema were independently associated with lower values for forced expiratory volume in one second and peripheral oxygen saturation (p values < 0.001). The relationships between mucus plug score and lung function outcomes were strongest in smokers with limited emphysema (p values <0.001). Compared to smokers with low mucus plug scores, those with high scores had worse COPD Assessment Test scores (17.4 ± 7.7 vs. 14.4 ± 13.3), more frequent annual exacerbations (0.75 ± 1.1 vs. 0.43 ± 0.85), and shorter 6-minute walk distance (329 ± 115 vs. 392 ± 117 meters)(p values < 0.001). CONCLUSION:Symptomatically silent mucus plugs are highly prevalent in smokers and independently associate with lung function outcomes. These data provide rationale for targeting mucus-high/emphysema-low COPD patients in clinical trials of muco-active treatments.
journal_name
Am J Respir Crit Care Medauthors
Dunican EM,Elicker BM,Henry T,Gierada DS,Schiebler ML,Anderson W,Barjaktarevic I,Barr RG,Bleecker ER,Boucher RC,Bowler RP,Christenson SA,Comellas A,Cooper CB,Couper D,Criner GJ,Dransfield M,Doerschuk CM,Drummond MB,doi
10.1164/rccm.202006-2248OCsubject
Has Abstractpub_date
2020-11-12 00:00:00eissn
1073-449Xissn
1535-4970pub_type
杂志文章abstract::In order to assess the usefulness of sputum analysis in studying plasma-protein exudation and local secretion of proteins in the airways, we measured specific proteins in the sputum sol phase (SSP) and sputum gel phase (SGP) from patients with stable asthma or chronic obstructive pulmonary disease (COPD). Protein leve...
journal_title:American journal of respiratory and critical care medicine
pub_type: 杂志文章
doi:10.1164/ajrccm.150.6.7952610
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journal_title:American journal of respiratory and critical care medicine
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journal_title:American journal of respiratory and critical care medicine
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journal_title:American journal of respiratory and critical care medicine
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journal_title:American journal of respiratory and critical care medicine
pub_type: 杂志文章,评审
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pub_type: 杂志文章,多中心研究,随机对照试验
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pub_type: 杂志文章,随机对照试验
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journal_title:American journal of respiratory and critical care medicine
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