Table 1:
Baseline characteristics and outcomes for the discovery and validation cohorts
| Discovery cohort (n=385) | Validation cohort (n=204) | p value | |
|---|---|---|---|
| Age, years | 63·6 (12·7) | 60·7 (11·6) | 0·0085 |
| Sex | |||
| Female | 228 (59%) | 124 (61%) | .. |
| Male | 157 (41%) | 80 (39%) | 0·71 |
| Race or ethnicity | |||
| White | 273 (71%) | 151 (74%) | 0·42 |
| Black | 15 (4%) | 26 (13%) | <0·0001 |
| Hispanic | 55 (14%) | 21 (10%) | 0·17 |
| Asian | 32 (8%) | 6 (3%) | 0·012 |
| Mixed or other | 10 (3%) | 0 | 0·02 |
| Years from diagnosis to blood draw | <0·001 | ||
| <1 | 292 (76%) | 44 (22%) | .. |
| 1 | 33 (9%) | 56 (27%) | .. |
| 2 | 19 (5%) | 42 (21%) | .. |
| 3 | 8 (2%) | 27 (13%) | .. |
| >3 | 33 (9%) | 35 (17%) | .. |
| Ever smoker | 259 (67%) | 114 (56%) | 0·0063 |
| ILD classification | |||
| CTD-ILD | 148 (38%) | 97 (48%) | 0·033 |
| Systemic sclerosis ILD | 42 (11%) | 30 (15%) | 0·67 |
| Rheumatoid arthritis ILD | 38 (10%) | 21 (10%) | 0·47 |
| Idiopathic inflammatory myopathy ILD | 42 (11%) | 26 (13%) | 0·79 |
| Other CTD-ILD | 26 (9%) | 20 (10%) | 0·55 |
| Chronic hypersensitivity pneumonitis | 185 (48%) | 57 (28%) | <0·0001 |
| Unclassifiable ILD | 52 (14%) | 50 (25%) | 0·0008 |
| Pulmonary function | |||
| FVC, % predicted | 64·4 (18·4) | 62·5 (19·2) | 0·23 |
| DLCO, % predicted | 46·7 (17·3) | 40·7 (17·7) | 0·0002 |
| High-resolution CT pattern | |||
| Definite or probable UIP | 75 (19%) | 60 (29%) | 0·0063 |
| Non-specific interstitial pneumonia | 111 (29%) | 101 (50%) | <0·0001 |
| Other pattern | 199 (52%) | 43 (21%) | <0·0001 |
| Outcomes | |||
| ILD progression | 164 (43%) | 92 (45%) | 0·56 |
| Death | 59 (15%) | 32 (16%) | 0·91 |
| Lung transplant | 6 (2%) | 12 (6%) | 0·0037 |
| ≥10% FVC decline | 99 (26%) | 48 (24%) | 0·56 |
| Months to progression | 6·7 (3·5–9·5) | 7·0 (4·0–9·3) | 0·69 |
Data are mean (SD), n (%), or median (IQR). ILD=interstitial lung disease. CTD-ILD=connective tissue disease-associated ILD. FVC=forced vital capacity. DLCO=diffusion capacity of the lung for carbon monoxide. UIP=usual interstitial pneumonia.