| Controls | Mild to moderate asthma | Severe asthma | Acute asthma | |
| Subjects (n) | 23 | 42 | 19 | 36 |
| Gender (M/F) | 13/10 | 17/25 | 6/13 | 10/26 |
| Age (y) (mean (SD)) | 44.3 (9.8) | 48.7 (13.8) | 47.5 (12.5) | 37.5 (16.9) |
| Atopic (n (%)) | 14 (60.9) | 36 (85.7) | 13 (68.4) | 17 (89.5)* |
| Smokers (n (%)) | 5 (21.7) | 1 (2.4) | 3 (15.8) | ND |
| FEV1 (% predicted) (mean (SD)) | 99.4 (14.4) | 87.9 (16.5) | 69.9 (18.6) | 79.6 (25.6)* |
| BMI (kg/m2) (mean (SD)) | 23.8 (3.5) | 25.2 (5.7) | 28.8 (7.0) | ND |
| Asthma medications | ||||
| Inhaled corticosteroids (n (%)) | 28 (67.7) | 18 (94.7) | 28 (80) | |
| Daily ICS dose (μg) (mean (SEM))† | 1013 (157) | 2317 (254) | 1566 (197) | |
| Oral corticosteroids (n (%))‡ | 0 | 7 (36.8) | 7 (19.4) | |
| β adrenoceptor agonists (n (%)) | 29 (69) | 18 (94.7)§ | 31 (88.6)¶ |
*Skin prick data were available for 19 acute patients, and FEV1 when stable was measured in 20 acute patients.
†Beclomethasone equivalent dose.
‡Use of oral corticosteroids at the time of blood sampling.
§One patient refused to use β2 agonists and used theophylline and sodium cromoglycate instead.
¶Five acute patients were not using β2 agonists regularly prior to the acute attack.
BMI, body mass index; FEV1, forced expiratory volume in 1 s; ICS, inhaled corticosteroid.