Table 1. Group characteristics
| COPD (n=49) | Smoking (n=74) | Non-smokers (n=55) | |
|---|---|---|---|
| Age (y) | 64±6 | 60±8* | 62±6 |
| Gender (% male) | 90 | 62 | 47** |
| Packyears | 49±24 | 34±21 | 0** |
| FEV1 (% pred) | 86±17 | 105±14 | 116±17** |
| FEV1/FVC (%) | 62±7 | 76±4 | 78±5† |
| Season (% winter) | 48 | 39 | 45 |
| PAsteps (steps/day) | 7647±3464 | 9440±3755 | 10762±3442† |
| PAmod (min/day) | 83±64 | 116±66 | 114±52† |
| VO2max (% pred) | 104±25 | 118±31 | 126±31† |
| 6MWT (% pred) | 90±10 | 92±8 | 103±11‡ |
Means ± std; *p<0.05 COPD vs smokers; **p<0.05 COPD vs smokers vs non-smokers; †p<0.05 COPD vs (non-)smokers; ‡p<0.05 non-smokers vs smokers/COPD.