Table 1.
Characteristics and lung function data in COPD patients, smoking controls (S) and non-smoking controls (NS).
| COPD | S | NS | |
|---|---|---|---|
| N (n) | 20 | 13 | 14 |
| Males (n) | 11 | 6 | 7 |
| Age (years) | 56 ± 5 | 55 ± 7 | 57 ± 4 |
| Pack-years (years) | 34 (24-43)### | 36 (27-37)††† | 0 |
| FEV1/FVC | 0.54 (0.38-0.52) ***### |
0.80 (0.76-0.81) | 0.84 (0.83-0.84) |
| FEV1/VC | 0.48 (0.52-0.62) ***### |
0.79 (0.75-0.83) | 0.77 (0.76-0.80) |
| FEV1 (L) | 1.58 (1.22-1.94) ***### |
2.89 (2.71-3.57) | 3.32 (2.75-3.94) |
| FEV1 (% predicted) | 53 (47-60)***### | 98 (95-104)† | 109 (106-121) |
| FEV1 reversibility (%) | 14 (4-19)***### | 4 (0-5) | 2 (0-3) |
| FEV1 reversibility (mL) | 190 (75-265)# | 90 (0-170) | 70 (8-105) |
Data are shown as mean and standard deviation for age, mean and inter quartile range for pack-years, median and inter quartile range for all others. Significant difference between groups is marked with * (COPD vs HS), # (COPD vs NS) and † (HS vs NS). The considered levels of significance were P < 0.05 (*, # or †), P < 0.01 (**, ## or ††) and P < 0.001 (***, ### or †††). FEV1: Forced expiratory volume in one second, measured post bronchodilation; FVC: Forced vital capacity; VC: Vital capacity.