Table 2.
Baseline clinical characteristics and outcomes between endotypes for discovery and validation cohorts.
| Characteristic | Discovery | Validation | ||||
|---|---|---|---|---|---|---|
| Class 1 | Class 2 | P-value | Class 1 | Class 2 | P-value | |
| N = 475 | N = 201 | N = 409 | N = 176 | |||
| Age (years) | 62 (±13) | 65 (±11) | 0.033 | 63 (±12) | 65 (±11) | 0.045 |
| Diagnosis | >0.9 | >0.9 | ||||
| CTD-ILD | 220 (46%) | 90 (45%) | 167 (41%) | 73 (41%) | ||
| fHP | 138 (29%) | 59 (29%) | 99 (24%) | 41 (23%) | ||
| IIP | 117 (25%) | 52 (26%) | 143 (35%) | 62 (35%) | ||
| Sex (female) | 296 (62%) | 119 (59%) | 0.4 | 224 (55%) | 96 (55%) | >0.9 |
| Race/Ethnicity | 0.064 | 0.11 | ||||
| White | 322 (68%) | 152 (76%) | 329 (80%) | 143 (81%) | ||
| Black | 36 (7.6%) | 12 (6.0%) | 57 (14%) | 22 (13%) | ||
| Hispanic | 65 (14%) | 27 (13%) | 1 (0.2%) | 4 (2.3%) | ||
| Other/Unknown | 52 (11%) | 10 (5.0%) | 22 (5.4%) | 7 (4.0%) | ||
| Smoking history | 170 (36%) | 85 (42%) | 0.11 | 199 (49%) | 94 (53%) | 0.3 |
| FVC (% predicted) | 68 (±19) | 60 (±19) | <0.001 | 70 (±20) | 60 (±17) | <0.001 |
| DLCO (% predicted) | 49 (±17) | 38 (±16) | <0.001 | 50 (±19) | 38 (±14) | <0.001 |
| Prior RTX/CYC exposure | 31 (6.5%) | 13 (6.5%) | >0.9 | 5 (1.2%) | 3 (1.7%) | 0.7 |
| Prednisone use at blood draw | 152 (32%) | 108 (54%) | <0.001 | 78 (19%) | 41 (23%) | 0.2 |
| IS use at blood draw | 105 (23%) | 51 (26%) | 0.4 | 80 (20%) | 46 (26%) | 0.076 |
| AF use at blood draw | 16 (3.4%) | 4 (2.0%) | 0.3 | 18 (4.4%) | 8 (4.5%) | >0.9 |
| 3-year transplant-free survival | 372 (78%) | 73 (36%) | <0.001 | 340 (83%) | 81 (46%) | <0.001 |
Data are shown as mean (±SD) and n (%). Abbreviations: AF, antifibrotic; CTD-ILD, connective tissue disease-associated interstitial lung disease; CYC, cyclophosphamide; DLCO, diffusion capacity of the lung for carbon monoxide; fHP, fibrotic hypersensitivity pneumonitis; FVC, forced vital capacity; IIP, idiopathic interstitial pneumonia; IS, immunosuppressant medication (mycophenolate, azathioprine, rituximab, or cyclophosphamide); RTX, rituximab.