Characteristics | Atopic asthma cases (n=156) | Non-atopic asthma cases (n=187) | ACOS cases (n=25) | Controls (n=932) |
Age, median (Q1, Q3) | 32.5 (25.5, 45.0) | 48.0 (39.0, 55.0) | 53.0 (48.0, 60.0) | 43.0 (34.0, 52.0) |
Gender, n (%) | ||||
Male | 57 (36.5) | 54 (28.9) | 17 (68.0) | 438 (47.0) |
Female | 99 (63.5) | 133 (71.1) | 8 (32.0) | 494 (53.0) |
Education, n (%)* | ||||
No vocational schooling | 23 (14.7) | 42 (22.7) | 10 (40.0) | 154 (16.6) |
Vocational course | 17 (10.9) | 36 (19.5) | 8 (32.0) | 104 (11.2) |
Vocational institution | 57 (36.5) | 45 (24.3) | 1 (4.0) | 271 (29.2) |
College level | 36 (23.1) | 43 (23.2) | 3 (12.0) | 261 (28.1) |
University or corresponding | 23 (14.7) | 19 (10.3) | 3 (12.0) | 138 (14.9) |
Smoking, n (%)† | ||||
Never | 79 (50.6) | 93 (50.3) | 2 (8.0) | 485 (52.2) |
Ex-smoker | 30 (19.2) | 47 (25.4) | 7 (28.0) | 205 (22.0) |
Current smoker | 47 (30.1) | 45 (24.3) | 16 (64.0) | 240 (25.8) |
Pets indoors sometimes, n (%) | 121 (77.6) | 125 (66.8) | 15 (60.0) | 616 (66.1) |
Indoor mould exposure at work or at home, n (%)‡ | 36 (23.1) | 38 (20.3) | 6 (24.0) | 193 (20.7) |
Secondhand smoke exposure, n (%) | ||||
Past 12 months exposure§ | 31 (19.9) | 40 (21.4) | 8 (32.0) | 166 (17.8) |
Cumulative lifetime exposure§¶ | ||||
No exposure | 60 (39.7) | 65 (36.5) | 12 (52.2) | 359 (40.3) |
<100 cigarette-years | 30 (19.9) | 39 (21.9) | 3 (13.0) | 206 (23.2) |
≥100 cigarette-years | 61 (40.4) | 74 (41.6) | 8 (34.8) | 325 (36.5) |
*Education missing for 4 controls and 2 cases of non-atopic asthma.
†Smoking missing for 2 controls and 2 cases of non-atopic asthma.
‡Mould exposure missing (answered ’do not know’) for 1 control.
§Combined home and workplace exposure.
¶Cumulative lifetime secondhand smoke exposure missing for 42 controls, for 19 cases of non-atopic asthma and for 5 cases of atopic asthma.
ACOS, asthma–COPD overlap syndrome.