Table 1.
—Patient Characteristics
| Characteristic | Nonsmokers (n = 15) | Smokers Without COPD (n = 12) | COPD (n = 21) |
| Age, y | 51 ± 12 | 52 ± 10 | 62 ± 9a,b |
| Sex, female (male) | 6 (9) | 7 (5) | 8 (13) |
| Pack-y | 0 ± 0 | 24 ± 17 | 60 ± 36c |
| Smoking status, current smoker (ex-smoker) | NA | 12 (0) | 9 (12) |
| FEV1, L | 3.06 ± 0.72 | 2.74 ± 0.86 | 1.76 ± 0.58b,d |
| FEV, % predicted | 97 ± 13 | 94 ± 7 | 59 ± 14c,d |
| FEV1/FVC, % | 80 ± 5 | 78 ± 4 | 58 ± 10c,d |
NA = not applicable.
a
P < .01 compared with nonsmokers.
b
P < .01 compared with smokers without COPD.
c
P < .001 compared with smokers without COPD.
d
P < .001 compared with nonsmokers.