Lung function
| Normal control | Smoker normal FOT | Smoker abnormal FOT | |
| Subjects | 7 | 7 | 9 |
| Pre-bronchodilator spirometry | |||
| FVC % pred | 100 (92–105) | 98 (93–111) | 96 (85–102) |
| FEV1 % pred | 95 (86–101) | 99 (89–106) | 84 (79–95) |
| FEV1/FVC | 79 (76–84) | 74 (69–75) | 72 (65–77)* |
| Post-bronchodilator spirometry | |||
| FVC % pred | 102 (96–107) | 96 (89–114) | 96 (91–101) |
| FEV1 % pred | 100 (84–104) | 97 (94–111) | 93 (81–102) |
| FEV1/FVC | 83 (79–89) | 74 (71–79) | 72 (71–83) |
| Plethysmography | |||
| Lung volumes | |||
| TLC % pred | 85 (80–88) | 97 (87–129)* | 103 (99–107)* |
| Resistance | |||
| Raw cmH2O·L−1·s−1 | 1.43 (1.23–1.60) | 1.54 (1.22–2.01) | 2.19 (1.16–2.30) |
| sGaw L·s−1·cmH2O−1·L−1 | 0.20 (0.83–0.21) | 0.19 (0.15–0.23) | 0.12 (0.10–0.21) |
| Diffusing capacity | |||
| DLCO/VA mL·min−1·mmHg−1·L−1 | 4.87 (4.44–5.27) | 4.06 (3.56–4.97) | 3.44 (3.18–3.92) |
| FOT | |||
| Resistance | |||
| R5 kPa·L−1·s−1 | 0.36 (0.29–0.38) | 0.33 (0.31–0.34) | 0.57 (0.45–0.59)*,# |
| R20 kPa·L−1·s−1 | 0.31 (0.27–0.34) | 0.28 (0.25–0.30) | 0.40 (0.35–0.47)*,# |
| R5–20 kPa·L−1·s−1 | 0.05 (0.03–0.06) | 0.05 (0.03–0.07) | 0.12 (0.05–0.18)*,# |
| Reactance | |||
| AX kPa·L−1 | 0.23 (0.13–0.45) | 0.21 (0.13–0.39) | 0.72 (0.43–1.82)*,# |
| X5 kPa·L−1·s−1 | −0.10 (−0.13–0.07) | −0.10 (−0.12–0.05) | −0.16 (−0.25–0.13)*,# |
| fres Hz | 12.6 (9.3–14.2) | 12.3 (9.6–14.3) | 18.7 (13.2–22.9)*,# |
Data are presented as n or median (interquartile range). FOT: forced oscillation technique; FVC: forced vital capacity; FEV1: forced expiratory volume in 1 s; TLC: total lung capacity; Raw: airway resistance; sGaw: specific airway conductance; DLCO: diffusing capacity of the lung for carbon monoxide; VA: alveolar volume; Rx: resistance at x Hz; AX: reactance area; X5: dynamic elastance at 5 Hz; fres: resonant frequency. *: p<0.05, compared with normal control group (Kruskal–Wallis); #: p<0.05, compared with smoker normal FOT group (Kruskal–Wallis).