Table 2.
Emphysema measurements of asthma, COPD, and control participants
| Controls (n=128) | Asthma (n=151) | COPD (n=125) | P-value | |
|---|---|---|---|---|
| %LAA-950, % | 2.79±2.37 | 6.19±6.79* | 15.84±11.90*,# | <0.001a |
| %LAA-910, % | 21.07±20.06 | 26.20±18.78** | 40.97±17.75*,# | <0.001a |
| LP10A, HU | −914.7±23.0 | −924.1±32.0* | −954.3±25.9*,# | <0.001a |
| LP15A, HU | −905.9±24.7 | −914.8±33.5* | −944.0±26.7*,# | <0.001a |
| Per high EI, % | 0 | 32 (21.2%) | 83 (66.4%) | <0.001b |
| Upper zone EI, % | 2.51±2.35 | 5.82±8.27 | 17.91±14.68 | NA |
| Middle zone EI, % | 3.16±2.52 | 6.42±6.64 | 14.72±11.54 | NA |
| Lower zone EI, % | 2.77±2.62 | 6.36±7.36 | 15.13±13.10 | NA |
| Emphysema distribution | ||||
| ULP, n (%) | 21 (16.4) | 27 (17.9) | 61 (48.8) | <0.001c |
| MHE, n (%) | 84 (65.6) | 70 (46.4) | 37 (39.6) | |
| LLP, n (%) | 23 (18.0) | 54 (35.8) | 27 (21.6) |
Notes: Data are presented as mean ± SD or n (%).
P<0.01,
P<0.05 versus controls;
P<0.01 versus asthma patients.
Analysis of Kruskal–Wallis test.
Analysis of Mann–Whitney U test.
Analysis of chi-square test.
Abbreviations: EI, emphysema index; LAA%-910, percentage of lung voxels with CT attenuation value below −910 HU; %LAA-950, percentage of lung voxels with CT attenuation value below −950 HU; LLP, lower-lung-zone predominance; LP10A, mean lung attenuation value at the 10th percentile on lung attenuation curve; LP15A, mean lung attenuation value at the 15th percentile on lung attenuation curve; MHE, middle/homogeneous distribution; NA, not available; SD, standard deviation; ULP, upper-lung-zone predominance.