| NS | HS | Asthma | COPD | Overlap | |
| Subjects n | 26 | 23 | 32 | 39 | 14 |
| Females/males n | 10/16 | 11/12 | 16/16 | 13/26 | 5/9 |
| Age years | 46.9±2.6 | 47.6±2.5 | 58.3±1.5 | 62.4±1.1 | 61.2±1.5 |
| BMI kg·m−2 | 28.2±1.0 | 26.9±1.0 | 27.5±1.0 | 25.5±0.7 | 28.3±1.9 |
| Smoking status | |||||
| Former smoker | 0 | 0 | 17 (53) | 13 (33) | 8 (57) |
| Current smoker | 0 | 23 (100) | 4 (13) | 26 (67) | 6 (43) |
| Pack-years | 0 | 25.8±3.7 | 16.1±3.8 | 47.8±3.8 | 36.9±6.1 |
| Allergy | 4 (15) | 9 (40) | 18 (56) | 11 (28) | 5 (36) |
| ICS use | 0 | 0 | 28 (88) | 13 (33) | 14 (100) |
| Postbronchodilator | |||||
| FVC L | 4.7±0.2 | 4.4±0.3 | 3.5±0.2 | 3.2±0.2 | 3.2±0.3 |
| FEV1 L | 3.9±0.2 | 3.5±0.2 | 2.6±0.1 | 1.9±0.1 | 1.9±0.2 |
| FEV1 % pred | 103.8±2.1 | 96.0±3.6 | 77.0±3.0 | 57.9±3.2 | 55.3±3.1 |
| FEV1/FVC | 83.9±1.1 | 80.1±1.3 | 80.9±1.7 | 62.6±2.4 | 69.9±4.1 |
| DLCO % pred | 93.8±4.6 | 89.4±2.8 | 87.8±5.6 | 62.9±4.2 | 66.8±5.2 |
| ΔFEV1# mL | 110±31 | 78±38 | 173±36 | 109±30 | 203±49 |
| ΔFEV1# % | 3.1±0.9 | 2.4±1.1 | 7.8±1.6 | 7.5±1.3 | 13.0±4.0 |
| PEF diurnal variability % | 28.1±2.0 | 17.2±1.8 | 37.9±4.8 | ||
| Differential sputum cell counts % | |||||
| Eosinophils | 1.5±0.8 | 0.9±0.6 | 6.3±1.9 | 1.4±0.5 | 8.3±3.5 |
| Neutrophils | 34.7±2.7 | 41.9±5.4 | 53.4±4.6 | 63.1±3.6 | 68.2±4.1 |
| Macrophages | 59.11±3.3 | 54.3±5.6 | 41.3±4.4 | 32.9±3.7 | 21.8±3.5 |
Data are presented as mean±sem or n (%), unless otherwise stated. NS: nonsmokers; HS: healthy smokers; COPD: chronic obstructive pulmonary disease; BMI: body mass index; ICS: inhaled corticosteroid; FVC: forced vital capacity; FEV1: forced expiratory volume in 1 s; % pred: % predicted; DLCO: diffusing capacity of the lung for carbon monoxide; Δ: change in; PEF: peak expiratory flow. #: improvement in FEV1 after 400 μg salbutamol.