Table 1.
Subject demographics and clinical characteristics of the derivation (LTRC) cohort by IIP subcategory
| Disease groupa | Control | All IIPs | IPF | INSIP | UF | RB-ILD | P value (IIP vs control) | P value (IIP subtypes) |
|---|---|---|---|---|---|---|---|---|
| Number | 50 | 167 | 119 | 17 | 13 | 11 | ||
| Age - mean (std dev) | 47.5 (16.4) | 60.9 (10.2) | 62.6 (8.7) | 57.2 (12.2) | 56.7 (16.4) | 52.2 (10.9) | <0.0001* | 0.0016*** |
| Gender – % male | 54 | 61 | 65 | 53 | 62 | 36 | 0.41** | 0.27** |
| Race - % Caucasian | 82 | 87 | 94 | 82 | 85 | 82 | 0.067** | 0.18** |
| Smoker – | <0.0001** | 0.12** | ||||||
| Current | 21 (42 %) | 3 (3 %) | 0 (0 %) | 1 (6 %) | 0 (0 %) | 1 (9 %) | ||
| Former | 7 (14 %) | 96 (55 %) | 70 (59 %) | 11 (65 %) | 6 (46 %) | 6 (55 %) | ||
| Never | 20 (40 %) | 58 (35 %) | 41 (34 %) | 4 (24 %) | 7 (54 %) | 4 (36 %) | ||
| Unknown | 2 (4 %) | 10 (7 %) | 8 (7 %) | 1 (6 %) | 0 (0 %) | 0 (0 %) | ||
| Pack years - mean (std dev)b | 22.1 (19.5) | 58.6 (103) | 69.9 (115) | 20.5 (23.8) | 21.8 (14.1) | 53.3 (30.8) | 0.080* | 0.37*** |
| St George’s score - mean (std dev) | NA | 48.3 (21.0) | 46.6 (22.2) | 50.9 (16.6) | 54.5 (20.6) | 37.8 (17.0) | NA | 0.24*** |
| Pre-BD FVC, %predicted - mean (std dev) | NA | 63.1 (19.1) | 61.3 (16.8) | 69.9 (22.2) | 59.7 (27.6) | 85.7 (13.1) | NA | 0.0005*** |
| DLCO, %predicted - mean (std dev) | NA | 48.4 (21.9) | 45.9 (20.3) | 58.7 (22.1) | 48.7 (16.6) | 77.1 (21.3) | NA | <0.0001*** |
aIIP = idiopathic interstitial pneumonia, IPF = idiopathic pulmonary fibrosis, UIP = usual interstitial pneumonia, iNSIP = idiopathic nonspecific interstitial pneumonia, UF = uncharacterized fibrosis, RB-ILD = respiratory bronchiolitis associated interstitial lung disease. Data not reported individually for cryptogenic organizing pneumonia (COP) (n = 3) and desquamative interstitial pneumonia (DIP) (n = 4) categories
bAverage for current and former smokers
*Two-tailed student’s t-test
**Fisher’s exact test
***One-way ANOVA