TABLE 2

Comparison of lung function measures between healthy subjects and chronic obstructive pulmonary disease (COPD) patients

HealthyCOPDp-value
Subjects2055
Age years60 (52–64)62 (56–69)0.34
Males922ns
FEV1/FVC0.76 (0.71–0.79)0.44 (0.39–0.55)<0.001
FEV1/FVC z-score−0.43 (−0.89–−0.08)−4.00 (−4.36–−2.82)<0.001
FEV1 L2.97 (2.45–3.43)0.75 (0.641–0.95)<0.001
FEV1 z-score−0.08 (−0.61–0.54)−4.38 (−4.87–−3.72)<0.001
VT mL629 (506–953)758 (614–960)0.28
TE/Ttot0.56 (0.53–0.58)0.63 (0.60–0.66)<0.001
TPTEF/TE0.32 (0.22–0.36)0.20 (0.16–0.29)<0.001
VmaxE/VmaxI0.88 (0.73–1.0)0.74 (0.6–0.86)<0.001
Rmean hPa·s·L−13.15 (2.79–3.49)5.13 (4.26–6.18)<0.001
RmeanE hPa·s·L−13.27 (2.79–3.93)5.42 (4.13–6.75)<0.001
RmeanI hPa·s·L−12.88 (2.30–3.27)4.67 (4.05–5.87)<0.001
ReE hPa·s·L−12.34 (2.07–2.78)5.43 (4.48–6.74)<0.001
ReI hPa·s·L−11.99 (1.69–2.32)3.25 (2.58–4.11)<0.001
Xmean hPa·s·L−10.11 (−0.31–0.27)−5.18 (−6.83–−3.61)<0.001
XmeanE hPa·s·L−10.13 (−0.30–0.23)−6.72 (−8.50–−4.22)<0.001
XmeanI hPa·s·L−10.07 (−0.2–0.26)−2.63 (−3.37–−1.67)<0.001
XeE hPa·s·L−10.29 (0.11–0.48)−4.89 (−6.43–−3.41)<0.001
XeI hPa·s·L−1−0.04 (−0.32–0.14)−1.58 (−2.30–−1.05)<0.001
ΔXI hPa·s·L−10.29 (0.24–0.49)−3.03 (−4.47–−1.97)<0.001
Xmin hPa·s·L−1−0.50 (−88–−0.13)−9.19 (−11.99–−6.44)<0.001
AXV hPa·s0.00 (−0.09–0.09)2.34 (1.32–3.05)<0.001
EFL index hPa·s·L−1−0.01 (−0.13–0.10)3.24 (2.09–5.51)<0.001
  • Data are presented as n or median (interquartile range), unless otherwise stated. FEV1: forced expiratory volume in 1 s; FVC: forced vital capacity; VT: tidal volume; ns: nonsignificant. Lung function variables are defined in table 1.