Table 2—

Quantitative high-resolution computed tomography parameters by sex, age and smoking groups

% Low-attenuation areas < -950 HUAWT-Pi10 cm#
COPD casesControlsCOPD casesControls
Subjects n462428438407
All subjects7.02 (2.23–17.80)0.52 (0.21–1.28)0.494±0.0330.477±0.029
Age yrs
 Current smokers4.860.350.4950.476
Current smokers
 <10 cigarettes·day−16.020.310.4800.473
 10–19.9 cigarettes·day−14.280.360.4990.473
 ≥20 cigarettes·day−15.330.260.5010.487
  • Data for all parameters are presented as median (25th–75th percentile) or mean±sd. Data for % low-attenuation areas < -950 HU are presented as median and for AWT-Pi10 (airway wall thickness for an airway with an internal perimeter of 10 mm) as mean. The p-values were calculated using Kruskall–Wallis (low-attenuation area) and ANOVA (AWT-Pi10). HU: Hounsfield units; COPD: chronic obstructive pulmonary disease. #: standardised measurement of airway wall thickness. The bold p-values indicate significance.