Table 3.
Imaging Characteristics
| Parameters | Never Smokers | Former Smokers | Current Smokers | P-value |
|---|---|---|---|---|
| n=65 | n=83 | n=115 | ||
| LC Whole (ml) | 4594.28±1332.85 | 5663.81±1305.35* | 6004.53±1252.95* | <0.001 |
| LC Right lung (ml) | 2495.24±712.45 | 3033.31±700.95* | 3201.49±655.4* | <0.001 |
| LC Left lung (ml) | 2099.03±643.76 | 2630.5±644.48* | 2824.56±605.5* | <0.001 |
| %LAA−950 Whole lung | 14.94±7.93 | 21.45±9.25* | 20.54±9.5* | <0.001 |
| %LAA−950 Right lung | 13.89 (9.26~18.75) | 21.93 (15.17~28.45) * | 20.73 (13.53~26.48) * | <0.001 |
| %LAA−950 Left lung | 13.67 (8.96~19.85) | 22.11 (14.33~27.57) * | 21.35 (12.29~26.83) * | <0.001 |
| MED Whole lung (HU) | −980.44 (−982.54~-979.23) | −983 (−984.8~-981.15) * | −982.23 (−984.3~-980.35) * | <0.001 |
| MED Right lung (HU) | −980.06 (−982.64~-978.72) | −982.84 (−984.71~-980.875) * | −981.69 (−984.24~-980.07) * | <0.001 |
| MED Left lung (HU) | −980.78 (−982.94~-979.9) | −983.3 (−984.74~-981.2) * | −982.6 (−984.79~-980.21) * | 0.001 |
| MLD Whole lung (HU) | −839.68 (−856.24~-817.42) | −852.92 (−871.94~-835.07) * | −857.25 (−873.4~-834.18) * | 0.005 |
| MLD Right lung (HU) | −841.27 (−856.14~-818.25) | −855.27 (−871.74~-835.4) * | −855.12 (−873.67~-834.98) * | 0.004 |
| MLD Left lung (HU) | −838.08 (−864.02~-815.32) | −852.12 (−870.95~-831.11) | −858.67 (−874.93~-836.64) * | 0.005 |
| HI Whole lung | 0.08±0.25 | 0.14±0.28 | 0.13±0.27 | 0.398 |
| HI Right lung | 0.08±0.29 | 0.16±0.3 | 0.17±0.29 | 0.16 |
| HI Left lung | −0.1±0.29 | −0.09±0.28 | −0.12±0.32 | 0.75 |
Note: *P < 0.05 compared with NS group.
Abbreviations: LC, lung capacity; %LAA−950, the extent of emphysema of CT attenuation value below −950 HU; MED, mean emphysema density; MLD, mean lung density; HI, emphysema heterogeneity index, when emphysema is equally distributed among the lobes or the full extent in the whole lung is < 1%, HI is near zero; otherwise, HI = (%LAA upper -%LAA lower)/(%LAA upper+%LAA lower)*100.