Comparison of pulmonary function tests, serum markers and chest computed tomography (CT) findings between patients with idiopathic pleuroparenchymal fibroelastosis (IPPFE) with usual interstitial pneumonia (UIP) and typical idiopathic pulmonary fibrosis (IPF)
| Variable | IPPFE with UIP | Typical IPF | p-value |
| Subjects n | 64 | 195 | |
| FVC % predicted | 66.7±16.9 | 78.5±18.8 | 0.0001 |
| FEV1 % predicted | 86.1±24.9 | 97.2±47.3 | 0.073 |
| TLC % predicted | 74.4±15.7 | 77.9±16.6 | 0.153 |
| RV % predicted | 90.6±27.3 | 82.9±21.9 | 0.026 |
| DLCO % predicted | 66.2±25.2 | 60.3±20.4 | 0.072 |
| CPI | 41.5±18.2 | 43.0±21.7 | 0.621 |
| KL-6 U·mL−1 | 823±485 | 1123±743 | 0.003 |
| SP-D ng·mL−1 | 283±162 | 293±234 | 0.742 |
| PaO2 mmHg | 84.1±13.4 | 80.8±13.1 | 0.087 |
| PaCO2 mmHg | 43.6±5.8 | 39.4±3.9 | <0.0001 |
| Fibrosis score | 1.7±0.7 | 1.6±0.6 | 0.953 |
| Extent of bronchiectasis | 1.8±0.8 | 1.6±0.7 | 0.106 |
| CT pattern: UIP/possible UIP/inconsistent with UIP | 169/22/4 |
Data are presented as mean±sd unless otherwise stated. FVC: forced vital capacity; FEV1: forced expiratory volume in 1 s; TLC: total lung capacity; RV: residual volume; DLCO: diffusing capacity of the lung for carbon monoxide; CPI: composite physiological index; KL-6: Krebs von den Lungen-6; SP-D: surfactant protein D; PaO2: arterial oxygen tension; PaCO2: arterial carbon dioxide tension.