Characteristics of healthy and asthma subjects
| Healthy subjects | Non-neutrophilic asthma (NNA) | Neutrophilic asthma (NA) | p-value | |
| Subjects n | 20 | 14 | 16 | |
| Age years | 33.6±2.0 | 42.2±3.7 | 51.8±3.9 | <0.01 NA versus healthy, >0.05 NA versus NNA |
| Sex M/F n | 7/13 | 6/8 | 8/8 | 0.33 NA versus healthy and NNA |
| FEV1 % predicted | 96.0±2.7 | 75.4±5.5 | 61.2±5.0 | <0.01 NA versus healthy, 0.07 NA versus NNA |
| BMI kg·m−2 | 29.7±1.3 | 27.5±1.5 | 29.3±1.5 | 0.55 NA versus healthy and NNA |
| FENO ppb | 23.2±3.3 | 36.3±5.9 | 52.7±13.1 | 0.02 NA versus healthy, >0.05 NA versus NNA |
| ACT score | N/A | 17.5±1.3 | 17.1±1.6 | 0.84 NA versus NNA |
| Inhaled corticosteroid use | None | High dose (3), low dose (11) | High dose (9), low dose (5), medium dose (1), unknown (1) | 0.11 NA versus NNA |
| Neutrophils % in BALF | 1.9±0.3 | 1.4±0.2 | 15.3±4.6 | <0.01 NA versus healthy and NNA |
| Eosinophils % in BALF | 0.5±0.2 | 1.8±0.7 | 3.0±0.9 | <0.01 NA versus healthy, >0.05 NA versus NNA |
| Macrophages % in BALF | 91.5±1.0 | 90.4±2.7 | 72.4±4.9 | <0.01 NA versus healthy and NNA |
| Lymphocytes % in BALF | 6.1±0.8 | 6.4±1.3 | 9.9±1.7 | 0.11 NA versus healthy and NNA |
| IL-8 pg·mL−1 in BALF | 24.8±1.5 | 41.8±5.8 | 138.5±42.7 | <0.01 NA versus healthy and NNA |
Data expressed as mean±sem unless otherwise stated. All subjects were nonsmokers. M: male; F: female; FEV1: forced expiratory volume in 1 s; BMI: body mass index; FENO: fractional exhaled nitric oxide; ACT: asthma control test; BALF: bronchoalveolar lavage fluid; IL-8: interleukin-8; N/A: not applicable.