Table 1.
Characteristics of healthy controls and subjects with chronic respiratory symptoms and PPF
| Symptomatic subjects with PPF (n = 209) | Healthy controls (n = 85) | P value | |
|---|---|---|---|
| Demographics | |||
| Age (years) | 39.53 ± 12.79 | 36.92 ± 10.21 | 0.067 |
| BMI (kg/m2) | 22.09 ± 3.12 | 22.68 ± 2.57 | 0.123 |
| Sex: male, n (%) | 97 (46.4) | 40 (47.1) | 0.920 |
| Spirometry | |||
| FEV1 (% predicted) | 104.61 ± 12.41 | 106.58 ± 10.73 | 0.201 |
| FVC (% predicted) | 105.90 ± 13.09 | 106.65 ± 12.85 | 0.656 |
| FEV1/FVC | 83.78 ± 6.97 | 85.16 ± 5.81 | 0.108 |
| FEF25–75% (% predicted) | 86.48 ± 22.71 | 93.02 ± 21.01 | 0.023 |
| FEF50% (% predicted) | 90.98 ± 22.95 | 100.53 ± 22.64 | 0.001 |
| FEF75% (% predicted) | 81.37 ± 30.57 | 85.50 ± 27.61 | 0.281 |
| IOS | |||
| R5 (kPa/L s) | 0.32 ± 0.07 | 0.28 ± 0.06 | < 0.001 |
| R20 (kPa/L s) | 0.29 ± 0.06 | 0.26 ± 0.06 | < 0.001 |
| R5–R20 (kPa/L s) | 0.0219 ± 0.0273 | 0.0193 ± 0.0238 | 0.449 |
| X5 (kPa/L s) | − 0.1009 ± 0.0279 | − 0.1007 ± 0.0280 | 0.966 |
| Fres (Hz) | 11.38 ± 2.58 | 10.49 ± 2.10 | 0.005 |
| AX (kPa/L) | 0.24 (0.17, 0.34) | 0.20 (0.14, 0.30) | 0.015 |
The data are presented as mean ± SD for normally distributed variables and median (interquartile range) for nonnormally distributed variables
BMI body mass index