Association of maximum exercise capacity with lung function
| Predictor variable | Change in VO2max (mL/min) | ||
| r2 | PE±SEM | P values | |
| RV/TLC (%) | 0.47 | −16±6 | 0.013 |
| FEV1/FVC (%) | 0.46 | −12±7 | 0.070 |
| FEV1 (L) | 0.46 | 149±78 | 0.059 |
| FEF25–75 (L/s) | 0.45 | −21±44 | 0.635 |
| FEF75 (L/s) | 0.46 | −109±76 | 0.151 |
| TLC (L) | 0.47 | 113±47 | 0.017 |
| RV (L) | 0.45 | −31±85 | 0.714 |
| FRC (L) | 0.47 | −15±58 | 0.801 |
| Slope of VFL (mL/W)* | 0.42 | −29±10 | 0.009 |
| 1% change in slope of %EFL (%/W)* | 0.40 | −3.52±1.39 | 0.017 |
| Slope of EELV (FRC) (mL/W)* | 0.27 | 16±18 | 0.390 |
| Slope of RV (mL/W)* | 0.26 | −7±19 | 0.701 |
| LAAexp −860 to −950† | 0.24 | −9±4 | 0.049 |
Association of maximum exercise capacity (VO2max) with lung function was estimated using the regression analyses with adjustment for age, sex, height and weight with inclusion of one lung function at a time based on the regression model: Work=β0+β1(age)+β2(sex)+β3(height)+β4(weight)+β5(lung function). n=179 unless otherwise noted. Significant p-values are shown in bold.
*n=32.
†n=23.
%EFL, per cent of expiratory flow limitation; EELV, end-expiratory lung volume; FEF25–75, maximum airflow at mid-lung volume; FEF75, maximum airflow at low-lung volume; FEV1, forced expiratory volume in 1 s; FRC, functional residual capacity; FVC, forced vital capacity; LAAexp −860 to −950, per cent low attenuation area between −860 and − 950 HU on RV scan representing radiographic gas trapping; PE±SEM, parameter estimate±SEM; r2, model fit; RV, residual volume; TLC, total lung capacity; VFL, volume of the tidal breath that is flow limited on expiration; VO2max, maximum oxygen uptake.