Table 9. AE predictive significance of serum cytokines/%FVC determined by Cox proportional hazard regression analysis.
| Parameters* | HR** | 95% CI | P value |
|---|---|---|---|
| Univariate analysis | |||
| IL-1β/%FVC | 1.257e9 | 0.000–1.037e44 | 0.610 |
| IL-ra/%FVC | 1.373 | 0.984–1.917 | 0.062 |
| IL-2/%FVC | 1.915e13 | 0.000–5.734e31 | 0.159 |
| IL-4/%FVC | 1.101e27 | 0.008–1.556e56 | 0.069 |
| IL-5/%FVC | 48.713 | 0.016–145,457.537 | 0.341 |
| IL-6/%FVC | 2.722 | 0.000–977,650,401 | 0.919 |
| IL-7/%FVC | 98,037.144 | 4.048–2.374e9 | 0.026 |
| IL-8/%FVC | 0.982 | 0.176–5.469 | 0.983 |
| IL-9/%FVC | 10.276 | 1.208–87.378 | 0.033 |
| IL-10/%FVC | 27,592.119 | 0.000–7.565e21 | 0.618 |
| IL-12/%FVC | 2.256 | 0.000–1,921,813.53 | 0.907 |
| IL-13/%FVC | 5,427,096.68 | 2.853–1.032e13 | 0.036 |
| IL-15/%FVC | 2.512 | 0.644–9.802 | 0.185 |
| IL-17/%FVC | 222,037,044 | 2.734–1.803e16 | 0.039 |
| Eotaxin (CCL11)/%FVC | 8.611 | 1.972–37.613 | 0.004 |
| b-FGF/%FVC | 54,703.892 | 17.649–169,554,985 | 0.008 |
| G-CSF/%FVC | 1.416 | 0.527–3.800 | 0.490 |
| GM-CSF/%FVC | 66,901,058.1 | 0.000–4.228e24 | 0.389 |
| IFNγ/%FVC | 5.156 | 0.005–4,880.085 | 0.639 |
| IP-10 (CXCL10)/%FVC | 1.042 | 0.945–1.150 | 0.408 |
| MCP-1(CCL2)/%FVC | 0.760 | 0.112–5.133 | 0.778 |
| MIP-1α (CCL3)/%FVC | 0.381 | 0.018–7.880 | 0.532 |
| PDGF-BB/%FVC | 1.134 | 1.052–1.221 | 0.001 |
| MIP-1β (CCL4)/%FVC | 0.982 | 0.891–1.084 | 0.723 |
| RANTES (CCL5)/%FVC | 1.001 | 0.996–1.006 | 0.738 |
| TNF-α/%FVC | 3.403 | 0.125–92.146 | 0.467 |
| VEGF-A/%FVC | 2.716 | 0.542–13.609 | 0.224 |
| Multivariate analysis with stepwise selection procedure | |||
| IL-13/%FVC | 902,694,187 | 108.785–7.491e15 | 0.011 |
| PDGF-BB/%FVC | 1.147 | 1.063–1.238 | <0.001 |
| Adjusted by mMRC (≥2 vs. <2) with stepwise procedure | |||
| PDGF-BB/%FVC | 1.133 | 1.045–1.228 | 0.003 |
| mMRC (≥2 vs. <2) | 4.116 | 1.692–10.015 | 0.002 |
*, cytokine levels were used as pg/mL; **, HR >1 means an increase in each continuous parameter indicating high risk of occurrence of acute exacerbation. AE, acute exacerbation; b-FGF, basic fibroblast growth factor; CCL, CC chemokine ligand; CI, confidence interval; CXCL, CXC chemokine ligand; G-CSF; granulocyte colony-stimulating factor; GM-CSF, granulocyte-macrophage colony-stimulating factor; HR, hazard ratio; HRCT, high-resolution computed tomography; IFN, interferon; IIP, idiopathic interstitial pneumonia; IL, interleukin; IP-10, IFN-γ inducible protein; MCP, monocyte chemotactic protein; MIP, macrophage inflammatory protein; mMRC, modified Medical Research Council score for shortness of breathe; PDGF, platelet-derived growth factor; RANTES, regulated on activation, normal T-cell expressed and secreted; TNF, tumor necrosis factor; VEGF, vascular endothelial growth factor.