Table 2. Comparison of characteristics between ILD patients with and without AE.
| Variable | AE (+) | No AE(-) | P-value |
|---|---|---|---|
| (n = 15) | (n = 68) | ||
| Number of patients, n (%) | 15 (18.1) | 68 (81.9) | |
| Age, years | 70.3 ± 5.8 | 67.6 ± 11.2 | .477 |
| Male, n (%) | 10 (66.7) | 44 (64.7) | .885 |
| Ever smokers, n (%) | 7 (46.7) | 43 (64.2) | .209 |
| BMI, kg/m2 | 23.9 ± 4.1 | 24.6 ± 3.3 | .368 |
| Interstitial lung disease | |||
| IPF, n (%) | 12 (80.0) | 45 (66.2) | .296 |
| CTD, n (%) | 3 (20.0) | 9 (13.2) | .500 |
| Pulmonary function | |||
| FVC, % predicted | 69.5 ± 13.1 | 74.9 ± 15.9 | .219 |
| DLco, % predicted | 52.5 ± 16.8 | 60.5 ± 16.8 | .179 |
| TLC, % predicted | 76.0 ± 13.4 | 71.6 ± 12.4 | .536 |
| Six-minute walk test | |||
| Distance, m | 355.9 ± 101.9 | 410.8 ± 96.8 | .084 |
| Baseline SpO2, % | 94.3 ± 2.3 | 96.2 ±2.4 | .009 |
| Lowest SpO2, % | 88.8 ± 5.5 | 90.9 ± 5.9 | .153 |
| Baseline IL-6, pg/mL | 35.5 ± 68.3 | 10.5 ± 17.5 | .057 |
| Peak IL-6*, pg/mL | 133.5 ± 205.9 | 21.1 ± 35.0 | < .001 |
| CRP, mg/dL | 7.9 ± 9.9 | 1.2 ± 2.5 | < .001 |
| WBC, cell/μL | 9,614.0 ± 4,169.3 | 7,759.7 ± 2,657.2 | .024 |
| LDH, IU/L | 317.0 ± 147.7 | 255.1 ± 67.0 | .226 |
Values are presented as mean ± standard deviation or number (%).
AE, acute exacerbation; BMI, body mass index; IPF, idiopathic pulmonary fibrosis; CTD, connective tissue disease-associated interstitial lung disease; FVC, forced vital capacity; DLco, diffusing capacity of the lungs for carbon monoxide; TLC, total lung capacity; SpO2, saturation of peripheral oxygen; IL-6, interleukin-6; CRP, C-reactive protein; WBC, white blood cell; LDH, Lactate dehydrogenase.
*Peak IL-6 –highest serum level of IL-6 among sequentially measured IL-6 during follow-up.