Total | Intermittent asthma | Mild persistent asthma | Moderate persistent asthma | Severe persistent asthma | p Value | |
PD20, μmol | 3.11±2.76 | 3.81±2.34 | 2.69±2.71 | 3.56±3.21 | 2.29±0.40 | 0.517 |
Bronchial reactivity indices | ||||||
DRS, %/μmol | 5.19±5.82 | 5.99±8.42 | 4.46±4.13 | 5.14±5.93 | 9.31±2.46 | 0.376 |
CIR | 0.44±0.58 | 0.37±0.63 | 0.49±0.51 | 0.36±0.64 | 0.96±0.12 | 0.218 |
BRI | 12.7±3.1 | 12.4±3.0 | 12.1±2.2 | 13.3±4.0 | 17.3±0.7† ‡ | 0.008 |
AQLQ | ||||||
Symptoms | 5.78±0.85 | 5.83±0.94 | 5.90±0.57 | 5.72±1.06 | 4.79±0.24 | 0.086 |
Activity limitation | 5.87±0.82 | 5.96±0.93 | 6.11±0.42 | 5.57±1.05§ | 5.14±0.05 | 0.008 |
Emotional function | 6.03±0.92 | 5.80±0.80 | 6.17±0.66 | 6.05±1.26 | 5.80±0.00 | 0.465 |
Environmental exposure | 5.87±0.78 | 5.68±1.17 | 6.07±0.58 | 5.81±0.67 | 5.25±0.29 | 0.080 |
Total | 5.86±0.73 | 5.85±0.83 | 6.04±0.42 | 5.73±0.92 | 5.13±0.14 | 0.052 |
↵* Data are mean±SD.
Comparisons between groups: †p=0.020 vs intermittent asthma; ‡p=0.007 vs mild persistent asthma; §p=0.024 vs mild persistent asthma.
AQLQ, Asthma Quality of Life Questionnaire; BRI, bronchial reactivity index; CIR, continuous index of responsiveness; DRS, dose–response slope; PD20, dose of methacholine that produced a 20% fall in forced expiratory volume at 1 s.