TABLE 1.
Comparison of case characteristics.
| Small airway dysfunction | Non-small airway dysfunction | P-value | |
|---|---|---|---|
| Case | 84 | 159 | |
| States (survive/death/lung transplantation) | 25/38/21 | 74/49/36 | 0.028 |
| Survive | 25 | 74 | 0.013 |
| Death | 38 | 49 | 0.035 |
| Lung transplantation | 21 | 36 | 0.751 |
| Male/female | 74/10 | 149/10 | 0.130 |
| Age | 62.75 ± 8.50 | 64.7 ± 7.46 | 0.164 |
| Smoking/Non-smoking | 56/28 | 118/41 | 0.215 |
| Fibrosis rate% | 15.76 ± 11.16 | 14.24 ± 10.84 | 0.291 |
| Emphysema rate% | 1.59 ± 3.15 | 0.98 ± 1.80 | 0.117 |
| Median survival time (months) | 34 ± 7.59 | 52 ± 5.34 | 0.028 |
| SpO2% | 94.27 ± 4.14 | 94.94 ± 4.78 | 0.052 |
| FVC | 2.17 ± 0.73 | 2.50 ± 0.72 | 0.002 |
| FVC pred% | 62.86 ± 19.32 | 74.60 ± 21.01 | <0.001 |
| FEV1 | 1.68 ± 0.50 | 2.15 ± 0.55 | <0.001 |
| FEV1 pred% | 60.89 ± 16.94 | 80.64 ± 21.01 | <0.001 |
| FEV1/FVC | 79.55 ± 9.82 | 86.90 ± 5.57 | <0.001 |
| FEF25 pred% | 67.00 ± 24.24 | 92.91 ± 23.72 | <0.001 |
| FEF50 pred% | 62.49 ± 22.79 | 114.83 ± 30.98 | <0.001 |
| FEF75 pred% | 39.9 ± 16.07 | 97.70 ± 44.22 | <0.001 |
| MMEF pred% | 44.84 ± 14.38 | 94.24 ± 25.61 | <0.001 |
| DLcopred% | 42.85 ± 25.00 | 55.44 ± 29.33 | 0.003 |
| CPI index | 50.54 ± 20.05 | 43.19 ± 20.47 | 0.014 |
| CT stage((I/II/III) | 13/54/17 | 36/99/24 | 0.317 |
| PF grade(a/b/c) | 26/40/18 | 74/62/23 | 0.055 |
| GAP stage | 31/36/17 | 88/48/23 | 0.010 |
Notes: Measurement data are presented as mean ± standard deviation (SD). Count data are presented as percentage or proportion. SpO2%, oxygen saturation of peripheral blood. SpO2 is the resting arterial oxygen saturation measured at fingertips. FVC, forced vital capacity; FVC% pred, the percentage of the actual FVC over the predicted FVC; FEV1, forced expiratory volume in one second. FEV1% pred, the percentage of the actual FEV1 over the predicted FEV1; DLco, diffusing capacity of the lung for carbon monoxide; DLco% pred, the percentage of the actual DLco over the predicted DLco; FEV1/FVC%, the percentage of FEV1 over FVC. Fibrosis Rate and Emphysema Rate calculated by AI according to the system established by Wu et al. (2022) FEF25 pred%, Forced expiratory flow at 25 of vital capacity; FEF50 pred%, Forced expiratory flow at 25 of vital capacity; FEF75 pred%, Forced expiratory flow at 75 of vital capacity; MMEF pred%, Maximal mid-expiratory flow; CT stage, The stage was determined by using AI according to the system established by Li HP et al. PF-based grade: The grade was determined by using the pulmonary function and physiological parameters (age, gender, FVC% pred, DLco% pred, and SpO2%) and following the CTPF model recommendation by Li HP et al. The grade was defined as: mild (a), moderate (b), and severe (c). GAP (gender, age, and physiologic variables) stage followed the recommendation by Brett Ley, and a higher stage represented a greater death risk. CPI: composite physiologic index. In 2002, Athol U. Wells and others proposed to use CPI, which combined chest CT and pulmonary functional parameters, to assess the severity of interstitial lung diseases (ILDs). A higher CPI represents a more severe ILD.