Normal | Asthma | COPD | p-value | |
Subjects n | 20 | 22 | 18 | |
Males | 8 | 8 | 12 | |
Age years | 32±10 | 59±17 | 66±9 | <0.001 |
Height cm | 169±11 | 164±10 | 170±6 | 0.1 |
Weight kg | 71±15 | 76±18 | 73±14 | 0.6 |
Spirometry | ||||
FEV1 % predicted | 100±14 | 67±24 | 61±25 | <0.001 |
FVC % predicted | 100±15 | 87±19 | 96±23 | 0.08 |
FEV1/FVC % | 84±6 | 61±14 | 47±11 | <0.001 |
FOT | ||||
Rrs at 5 Hz hPa·s ·L−1 | 2.6 (2.3–3.5) | 5.2 (4.2–6.9) | 4.7 (4.0–6.8) | <0.001 |
Rrs at 5 Hz % predicted | 100 (83–125) | 170 (128–196) | 194 (151–253) | <0.001 |
Xrs at 5 Hz hPa·s·L−1 | −1.1 (−1.2–−0.8) | −2.3 (−5.0–−1.6) | −3.3 (−6.0–−1.6) | <0.001 |
Xrs at 5 Hz % predicted | 115 (78–135) | 185 (133–307) | 320 (144–530) | <0.001 |
Respiratory rate min−1 | 13.1±4.2 | 14.5±3.8 | 16.2±3.5 | 0.06 |
Data are shown as mean±sd or median (interquartile range), unless otherwise stated. Forced oscillation technique (FOT) parameters are reported for the default duration setting of 16 s. p-values were obtained from a one-way ANOVA or Kruskal–Wallis (non-parametric ANOVA). FEV1: forced expiratory volume in 1 s; FVC: forced vital capacity; Rrs: total respiratory system resistance; Xrs: total respiratory system reactance.