Characteristics of study participants
| SAn | Subjects n | SAs | Subjects n | MMA | Subjects n | HC | Subjects n | p-value | |
| Subjects n | 49 | 18 | 36 | 33 | |||||
| Age years | 48.6±14.36 | 49 | 51.9±8.35 | 18 | 38.3±13.70 | 36 | 37.6±13.77 | 44 | 10−5 |
| Female n (%) | 25 (51) | 49 | 7 (39) | 18 | 21 (58) | 36 | 16 (36) | 44 | 0.19 |
| Atopy n (%) | 35 (71) | 48 | 12 (67) | 18 | 27 (75) | 36 | 14 (32) | 44 | 10−4 |
| Total IgE IU·mL−1 | 318.1±445.6 | 49 | 623.6±1565.6 | 17 | 281.0±701.7 | 36 | 64.0±104.7 | 42 | 0.041 |
| On oral corticosteroids n (%) | 19 (38.8) | 45 | 9 (50.0) | 17 | 0 | 36 | NA | 0.58 | |
| On inhaled corticosteroids n (%) | 100% | 49 | 100% | 18 | 100% | 36 | NA | ||
| FEV1 % pred | 74.5 (33.1) | 49 | 69.5 (18.1) | 18 | 95.1 (21.4) | 36 | 100.7 (13.3) | 44 | 10−14 |
| FEV1/FVC | 78.8 (3.6) | 49 | 78.7 (2.3) | 18 | 81.8 (4.3) | 36 | 82.3 (3.4) | 44 | 0.004 |
| FVC % pred | 90.5 (25.4) | 49 | 92.9 (13.6) | 18 | 109.7 (25.9) | 36 | 110.3 (11.4) | 44 | 10−4 |
| FEV1 % increase post-salbutamol | 7.14 (13.7) | 49 | 13.7 (7.8) | 18 | 8.2 (9.9) | 34 | NA | 0.02 | |
| FeNO ppb | 32.5 (37.0) | 45 | 20.0 (17.5) | 17 | 21.0 (40.1) | 36 | 16.3 (14.8) | 42 | 0.005 |
| Blood eosinophils cells·μL−1 | 200.0 (300.0) | 49 | 200.0 (52.5) | 18 | 200.0 (200.0) | 36 | 100 .0 (102.5) | 44 | 0.018 |
| Sputum eosinophils % | 1.4 (15.4) | 21 | 0.8 (12.9) | 7 | 0.6 (2.7) | 15 | 0.0 (0.2) | 25 | 0.028 |
| BMI kg·m−2 | 30.6±6.3 | 49 | 29.1±6.2 | 18 | 26.4±4.7 | 36 | 24.8±3.3 | 44 | 10−6 |
| Exacerbations n | 2.5±2.0 | 48 | 2.3±1.7 | 18 | 0.36±0.79 | 36 | NA | 10−7 | |
| ACQ5 | 1.9±1.1 | 39 | 2.3±1.2 | 13 | 0.9±0.7 | 35 | NA | 10−6 | |
| Nasal polyps n (%) | 18 (40.1) | 44 | 7 (41.2) | 17 | 2 (5.8) | 34 | 3 (21) | 14 | 0.003 |
Data are presented as n, mean±sd or median (interquartile range), unless otherwise stated. SAn: severe nonsmoking asthma; SAs: smokers and ex-smokers with severe asthma; MMA: mild–moderate nonsmoking asthma; HC: healthy nonsmoking controls; FEV1: forced expiratory volume in 1 s; FVC: forced vital capacity; FeNO: exhaled nitric oxide fraction; BMI: body mass index; ACQ5: 5-item asthma control questionnaire; NA: not applicable.