Table 1. Patient characteristics.
| NP (n=67) † | P (n=18)c | p-values | |
|---|---|---|---|
| Age, yr | 64.8 (41.9–84.0) | 63.5 (44.0–78.0) | 0.767 a |
| BMI, kg/m2 | 22.7 (17.2–31.6) | 23.7 (16.1–26.9) | 0.519 a |
| Exposure period, yr | 18.2 (7.0–37.0) | 16.5 (5.0–35.0) | 0.198 a |
| Ex-exposure period, yr | 18.0 (0.5–42.0) | 18.8 (2.0–31.0) | 0.214 a |
| %FVC predicted | 91.5 (61.3–125.6) | 89.7 (62.3–112.2) | 0.250 a |
| %FEV1 predicted | 86.8 (41.9–129.2) | 83.6 (50.6–110.4) | 0.268 a |
| %FEV1/FVC ratio | 71.3 (65.2–76.1) | 66.7 (43.0–81.8) | 0.464 a |
| Smoking, N (%) | |||
| Never | 7 (10.4) | 4 (22.2) | 0.405 b |
| Past | 32 (47.8) | 8 (44.4) | |
| Current | 28 (41.8) | 6 (33.3) |
† NP, CWP subjects without progression; P, CWP subjects with progression. a Calculated by Mann-Whitney U test, median (range). b Calculated by χ2-test, number of cases (%). c Three-year progression was evaluated by paired comparison of chest radiographs. Category 0 (3 subjects): 0/0 (2) to 1/0, 0/1 (1) to 1/1. Category I (8 subjects): 1/0 (2) to 1/1, 1/1 (3) to 1/2, 1/1 (2) to 2/1, 1/2 (1) to 2/1. Category II (7 subjects): 2/1 (3) to 2/2, 2/2 (3) to 4A, 2/3 (1) to 3/2.