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

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


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.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Case-Control Studies
  • Cohort Studies
  • Female
  • Forced Expiratory Volume
  • Humans
  • Male
  • Middle Aged
  • Phenotype
  • Pulmonary Disease, Chronic Obstructive / complications*
  • Pulmonary Disease, Chronic Obstructive / diagnostic imaging*
  • Pulmonary Disease, Chronic Obstructive / physiopathology
  • Quality of Life*
  • Smoking
  • Tomography, X-Ray Computed