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. 2020 Jul;158(1):121-130.
doi: 10.1016/j.chest.2019.12.046. Epub 2020 Feb 1.

Luminal Plugging on Chest CT Scan: Association With Lung Function, Quality of Life, and COPD Clinical Phenotypes

Yuka Okajima  1 , Carolyn E Come  2 , Pietro Nardelli  3 , Sushil K Sonavane  4 , Andrew Yen  5 , Hrudaya P Nath  6 , Nina Terry  6 , Scott A Grumley  6 , Asmaa Ahmed  6 , Seth Kligerman  5 , Kathleen Jacobs  5 , David A Lynch  7 , Barry J Make  8 , Edwin K Silverman  9 , George R Washko  2 , Raúl San José Estépar  3 , Alejandro A Diaz  2
Affiliations

Luminal Plugging on Chest CT Scan: Association With Lung Function, Quality of Life, and COPD Clinical Phenotypes

Yuka Okajima et al. Chest. 2020 Jul.

Abstract

Background: Mucous exudates occluding the lumen of small airways are associated with reduced lung function and mortality in subjects with COPD; however, luminal plugs in large airways have not been widely studied. We aimed to examine the associations of chest CT scan-identified luminal plugging with lung function, health-related quality of life, and COPD phenotypes.

Methods: We randomly selected 100 smokers without COPD and 400 smokers with COPD from the COPDGene Study. Luminal plugging was visually identified on inspiratory CT scans at baseline and 5-year follow-up. The relationships of luminal plugging to FEV1, St. George's Respiratory Questionnaire (SGRQ) score, emphysema on CT scan (defined as the percentage of low attenuation area < 950 Hounsfield units [%LAA-950]), and chronic bronchitis were assessed using linear and logistic multivariable analyses.

Results: Overall, 111 subjects (22%) had luminal plugging. The prevalence of luminal plugging was higher in subjects with COPD than those without COPD (25% vs 10%, respectively; P = .001). In subjects with COPD, luminal plugging was significantly associated with FEV1 % predicted (estimate, -6.1; SE, 2.1; P = .004) and SGRQ score (estimate, 4.9; SE, 2.4; P = .04) in adjusted models. Although luminal plugging was associated with log %LAA-950 (estimate, 0.43; SE, 0.16; P = .007), its relationship with chronic bronchitis did not reach statistical significance (P = .07). Seventy-three percent of subjects with COPD with luminal plugging at baseline had it 5 years later.

Conclusions: In subjects with COPD, CT-identified luminal plugging is associated with airflow obstruction, worse health-related quality of life, and emphysema phenotype. This imaging feature may supplement the current clinical assessment of chronic mucus hypersecretion in COPD.

Keywords: COPD; CT scan; airway obstruction; luminal; mucus; plugging; smokers.

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Figures

Figure 1
Figure 1
A-B, CT scan findings of luminal plugging. (A) An axial image shows a luminal plug as a round opacity occluding the lumen of a branch of the left posterior basal bronchopulmonary segment (arrow). (B) The sagittal image shows luminal plugs as tubular opacities within the same airway (arrows).
Figure 2
Figure 2
The percentage of subjects with luminal plugging at phase 1 of the COPDGene Study. The bars represent the percentage of subjects with luminal plugging in those without COPD and those with COPD by spirometric GOLD stage. Note that the percentage of subjects with luminal plugging increased with the spirometric GOLD stage. The percentage for each bar was calculated using 100 study subjects for the non-COPD group and each GOLD stage except for overall subjects with COPD, where it was calculated with 400. GOLD = Global Initiative for Chronic Obstructive Lung Disease.
Figure 3
Figure 3
Distribution of CT scan-identified luminal plug scores at phases 1 (n = 111) and 2 (n = 52) of the COPDGene Study. Subjects without luminal plugging were not included.
Figure 4
Figure 4
(A) FEV1 % predicted, (B) FEF25%-75%, and (C) SGRQ total score among subjects with COPD by luminal plug status at phase 1. The box plots show the median (horizontal line in the middle of the box), mean (diamond), and 25th and 75th percentiles (bottom and top lines of the box) of FEV1 % predicted, FEF25%-75%, and SGRQ total score. The whiskers represent the upper and lower values (1.5 times above the 75th percentile and below the 25th percentile, respectively). P < .0001 for the difference in FEV1 % predicted, FEF25%-75%, and SGRQ between those with and without luminal plugging in univariate analysis. See text for details in adjusted models for these outcomes. FEF25%-75% = forced expiratory flow at 25% to 75% of the FVC; SGRQ = St. George’s Respiratory Questionnaire.
Figure 5
Figure 5
Five-year changes in luminal plugging presence for the whole lung and by lobe in all study subjects with both phase 1 and phase 2 CT scans available (n = 238). The bars show the percentage of subjects by group as follows: persistent negative (no luminal plugging on phase 1 and 2 CT scans); persistent positive (luminal plugging on phase 1 and 2 CT scans); newly formed (no luminal plugging on phase 1 CT scan and luminal plugging on phase 2 CT scan); and resolved (luminal plugging on phase 1 CT scan and no luminal plugging on phase 2 CT scan). LIN = lingula; LLL = left lower lobe; LUL = left upper lobe; RLL = right lower lobe; RML = right middle lobe; RUL = right upper lobe.
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References

    1. Burgel P.R., Martin C. Mucus hypersecretion in COPD: Should we only rely on symptoms? Eur Respir Rev. 2010;19(116):94–96. - PMC - PubMed
    1. Hogg J.C., Chu F., Utokaparch S. The nature of small-airway obstruction in chronic obstructive pulmonary disease. N Engl J Med. 2004;350(26):2645–2653. - PubMed
    1. Hogg J.C., Chu F.S., Tan W.C. Survival after lung volume reduction in chronic obstructive pulmonary disease: insights from small airway pathology. Am J Respir Crit Care Med. 2007;176(5):454–459. - PMC - PubMed
    1. Nakano Y., Wong J.C., de Jong P.A. The prediction of small airway dimensions using computed tomography. Am J Respir Crit Care Med. 2005;171(2):142–146. - PubMed
    1. Dunican E.M., Elicker B.M., Gierada D.S. Mucus plugs in patients with asthma linked to eosinophilia and airflow obstruction. J Clin Invest. 2018;128(3):997–1009. - PMC - PubMed

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