Clinical characteristics and prevalence of asthma–COPD overlap in groups of different occupational exposure to vapours, gases, dusts or fumes (VGDF)
| No occupational exposure to VGDF | Occupational exposure to VGDF | p-value | |
| Patients n | 150 | 44 | |
| Asthma–COPD overlap | 21 (14) | 13 (30) | 0.024¶ |
| Age years | 57.3±13.3 | 62.3±13.9 | 0.030¶ |
| BMI kg·m−2 | 27.7 (24.2–30.8) | 29.6 (25.4–32.0) | 0.057 |
| Males | 50 (33) | 31 (71) | <0.001¶ |
| Allergic rhinitis or conjunctivitis | 90 (62) | 28 (65) | 0.723 |
| ICS in daily use | 120 (80) | 33 (75) | 0.530 |
| Smoking history ≥10 pack-years | 47 (31.3) | 19 (43.2) | 0.152 |
| Obstructive asthma# | 15 (10) | 5 (11) | 0.782 |
Data are presented as n (%), mean±sd or median (interquartile range), unless otherwise stated. BMI: body mass index; ICS: inhaled corticosteroids. #: <10 pack-years and forced expiratory volume in 1 s/forced vital capacity ratio <0.7; ¶: p<0.05.