Lung function in community-based current asthma population by severity (n = 259*)
| Lung function measurements† | Intermittent(n = 79) | Mild persistent(n = 72) | Moderate persistent(n = 67) | Severe persistent(n = 41) | Current asthma total(n = 259) |
| FEV1 pre-BD (l) | 3.05 (2.93 to 3.17) | 2.96 (2.83 to 3.08) | 2.81 (2.68 to 2.94) | 2.65 (2.48 to 2.82) | 2.99 (2.93 to 3.06) |
| FEV1 post-BD (l) | 3.20 (3.09 to 3.32) | 3.11 (2.99 to 3.22) | 3.03 (2.91 to 3.15) | 2.84 (2.68 to 2.99) | 3.17 (3.11 to 3.23) |
| FVC pre-BD (l) | 4.10 (3.97 to 4.23) | 3.98 (3.85 to 4.11) | 4.00 (3.86 to 4.14) | 3.79 (3.61 to 3.97) | 4.12 (4.05 to 4.19) |
| FVC post-BD (l) | 4.20 (4.08 to 4.33) | 4.08 (3.95 to 4.21) | 4.12 (3.98 to 4.25) | 3.89 (3.72 to 4.06) | 4.23 (4.16 to 4.29) |
| FEV1/FVC pre-BD (%) | 74.4 (72.5 to 76.2) | 74.1 (72.1 to 76.0) | 70.6 (68.6 to 72.7) | 70.0 (67.4 to 72.6) | 72.6 (71.6 to 73.6) |
| FEV1/FVC post-BD (%) | 76.2 (74.3 to 78.0) | 76.5 (74.6 to 78.4) | 74.1 (72.1 to 76.2) | 73.3 (70.7 to 75.8) | 75.2 (74.3 to 76.1) |
| BD reversibility‡, n (%) | 8 (10.1%) | 10 (13.9%) | 14 (20.9%) | 8 (19.5%) | 40 (15.4%) |
Values shown are mean (95% CI).
BD, bronchodilator; FEV1, forced expiratory volume in 1 s; FVC, forced vital capacity.
*Restricted to participants with current asthma with available lung function measurements.
†Adjusted for adequate preventer medication use, age, gender, smoking status, height and weight.
‡Defined according to the ATS criteria and a positive response was defined as ⩾12% improvement in FEV1 and an absolute improvement of ⩾0.2 l.