Baseline characteristics of all patients in the internal cohort separated by randomly generated derivation and validation sets
| All patients | Derivation set | Validation set | |
| N=562 | N=281 | N=281 | |
| Age (years) | 72 (66, 77) | 72 (66, 77) | 71 (66, 76) |
| Gender, women | 129 (23.0) | 80 (28.5) | 49 (17.4) |
| Race, non-white | 126 (22.4) | 67 (23.8) | 59 (21.0) |
| Body mass index (kg/m2) | 29.0±6.3 | 29.3±6.7 | 28.7±5.8 |
| Comorbid disease | |||
| Smoking status ever | 368 (65.5) | 179 (63.7) | 189 (67.3) |
| Diabetes mellitus | 115 (20.5) | 58 (20.6) | 57 (20.3) |
| Hypertension | 264 (47.0) | 121 (43.1) | 143 (50.9) |
| Cardiovascular disease | 178 (31.7) | 88 (31.3) | 90 (32.0) |
| Severe OSA | 128 (22.8) | 73 (26.0) | 55 (19.6) |
| Lung cancer | 10 (1.8) | 3 (1.1) | 7 (2.5) |
| Measures of IPF severity and management considerations | |||
| FVC (%) predicted | 65.6±19.1 | 66.4±19.2 | 64.8±18.9 |
| FEV1/FVC (%) | 83.0 (78.0, 87.0) | 82.0 (77.0, 87.0) | 83.0 (78.0, 86.0) |
| DLCO (%) predicted | 41.0±15.4 | 41.4±15.4 | 40.7±15.4 |
| DLCO not performed | 54 (9.6) | 23 (8.2) | 31 (11.0) |
| 6MWD (m) | 366 (262, 445) | 370 (257, 447) | 357 (268, 442) |
| Surgical lung biopsy | 177 (31.5) | 93 (33.1) | 84 (29.9) |
| Antifibrotic therapy* | 330 (58.7) | 156 (55.5) | 174 (61.9) |
| Pirfenidone | 200 (35.6) | 89 (31.7) | 111 (39.5) |
| Nintedanib | 165 (29.4) | 84 (29.9) | 81 (28.8) |
| Exertional hypoxia | 228 (40.6) | 110 (39.1) | 118 (42.0) |
| Prescribed oxygen | 133 (58.3) | 67 (23.8) | 66 (23.5) |
| Observed desaturation† | 95 (41.7) | 45 (16.0) | 50 (17.8) |
| GAP stage‡ | |||
| 1 | 115 (20.5) | 63 (22.4) | 52 (18.5) |
| 2 | 278 (49.5) | 142 (50.5) | 136 (48.4) |
| 3 | 169 (30.1) | 76 (27.0) | 93 (33.1) |
Data presented as mean±SD, median (25th percentile, 75th percentile) or n (%).
*Antifibrotic therapy for at least 6 months (some patients transitioned between therapies).
†Observed desaturation during 6 min walk test in the absence of a prior oxygen prescription.
‡GAP stage as classified by the original GAP index proposed and validated by Ley et al. 5
DLCO, diffusion capacity for carbon monoxide; FVC, forced vital capacity; GAP, gender-age-physiology; 6MWD, 6 min walk test distance; OSA, obstructive sleep apneoa.