Quantitative CT Measures of Bronchiectasis in Smokers

Chest. 2017 Jun;151(6):1255-1262. doi: 10.1016/j.chest.2016.11.024. Epub 2016 Nov 24.


Background: Bronchiectasis is frequent in smokers with COPD; however, there are only limited data on objective assessments of this process. The objective was to assess bronchovascular morphology, calculate the ratio of the diameters of bronchial lumen and adjacent artery (BA ratio), and identify those measurements able to discriminate bronchiectasis.

Methods: We collected quantitative CT (QCT) measures of BA ratios, peak wall attenuation, wall thickness (WT), wall area, and wall area percent (WA%) at matched fourth through sixth airway generations in 21 ever smokers with bronchiectasis (cases) and 21 never-smoking control patients (control airways). In cases, measurements were collected at both bronchiectatic and nonbronchiectatic airways. Logistic analysis and the area under receiver operating characteristic curve (AUC) were used to assess the predictive ability of QCT measurements for bronchiectasis.

Results: The whole-lung and fourth through sixth airway generation BA ratio, WT, and WA% were significantly greater in bronchiectasis cases than control patients. The AUCs for the BA ratio to predict bronchiectasis ranged from 0.90 (whole lung) to 0.79 (fourth-generation). AUCs for WT and WA% ranged from 0.72 to 0.75 and from 0.71 to 0.75. The artery diameters but not bronchial diameters were smaller in bronchiectatic than both nonbronchiectatic and control airways (P < .01 for both).

Conclusions: Smoking-related increases in the BA ratio appear to be driven by reductions in vascular caliber. QCT measures of BA ratio, WT, and WA% may be useful to objectively identify and quantify bronchiectasis in smokers.

Trial registry: ClinicalTrials.gov; No.: NCT00608764; URL: www.clinicaltrials.gov.

Keywords: COPD; CT; bronchiectasis; smoking.

Publication types

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

MeSH terms

  • Aged
  • Area Under Curve
  • Bronchi / diagnostic imaging*
  • Bronchi / physiopathology
  • Bronchial Arteries / diagnostic imaging
  • Bronchiectasis / diagnostic imaging*
  • Bronchiectasis / epidemiology
  • Bronchiectasis / physiopathology
  • Case-Control Studies
  • Comorbidity
  • Female
  • Forced Expiratory Volume
  • Humans
  • Logistic Models
  • Lung / diagnostic imaging
  • Lung / physiopathology
  • Male
  • Middle Aged
  • Pulmonary Disease, Chronic Obstructive / diagnostic imaging*
  • Pulmonary Disease, Chronic Obstructive / epidemiology
  • Pulmonary Disease, Chronic Obstructive / physiopathology
  • Pulmonary Emphysema / diagnostic imaging
  • Pulmonary Emphysema / epidemiology
  • Pulmonary Emphysema / physiopathology
  • ROC Curve
  • Severity of Illness Index
  • Smoking*
  • Tomography, X-Ray Computed
  • Total Lung Capacity
  • Vital Capacity

Associated data

  • ClinicalTrials.gov/NCT00608764