| Parameters | HR (95% CI) | p-value |
| Univariate Cox analysis | ||
| Age | 1.021 (0.997–1.047) | 0.093 |
| Male sex | 0.921 (0.563–1.506) | ns |
| Smoking | 0.629 (0.407–0.972) | 0.037 |
| PFT % pred | ||
| FVC | 0.975 (0.960–0.989) | 0.001 |
| DL,CO | 0.981 (0.967–0.994) | 0.005 |
| TLC | 0.970 (0.953–0.987) | 0.001 |
| BAL | ||
| Macrophages | 0.991 (0.975–1.008) | ns |
| Lymphocytes | 1.001 (0.977–1.025) | ns |
| Neutrophils | 1.010 (0.989–1.031) | ns |
| Eosinophils | 0.994 (0.929–1.064) | ns |
| CRP | 0.786 (0.380–1.622) | ns |
| Steroids with/without cytotoxic agents# | 1.045 (0.682–1.602) | ns |
| Multivariate Cox analysis¶ | ||
| Smokers | 0.585 (0.342–1.001) | 0.050 |
| FVC % pred | 0.979 (0.964–0.995) | 0.011 |
HR: hazard ratio; PFT: pulmonary function test; FVC: forced vital capacity; % pred: % predicted; DL,CO: diffusing capacity of the lung for carbon monoxide; TLC: total lung capacity; BAL: bronchoalveolar lavage; CRP: C-reactive protein; ns: nonsignificant. #: within 30 days prior to RD; ¶: TLC % pred was excluded from the multivariate analysis due to the close correlation between FVC % pred and TLC % pred (r = 0.765; p<0.001).