Table 1. Classification of asthma severity according to NAEPP recommendation*.
| Components of severity | Mild intermittent | Mild persistent | Moderate persistent | Severe persistent | ||
|---|---|---|---|---|---|---|
| Impairment | ||||||
| Days with symptoms | ≤ 2 days/week | > 2 days/week, but not daily | Daily | Throughout the day | ||
| Nighttime awakenings | ≤ 2 times/month | 3–4 times/month | > 1 times/week, but not nightly | Often 7 times/week | ||
| Short-acting beta2-agonist use for symptom control | ≤ 2 days/week | > 2 days/week, but not daily† | Daily | Several times per day | ||
| Interference with normal activity | None | Minor limitation | Some limitation | Extremely limited | ||
| Lung function | ||||||
| - FEV1 (predicted) or peak flow (personal best) | Normal FEV1 between exacerbations > 80% | > 80% | 60%–80% | < 60% | ||
| - FEV1/FVC | > 85% | > 80% (≥ 85% in children ≥ 12 years of age) | 75%–80% (FEV1/FVC reduced 5% in children ≥ 12 years of age) | < 75% (FEV1/FVC reduced > 5% in children ≥ 12 years of age) | ||
| Risk | ||||||
| Exacerbations requiring oral systemic corticosteroids (consider severity and interval since last exacerbation) | 0–1 /year | ≥ 2 times/year | - | - | ||
FEV1, forced expiratory volume in 1 second; NAEPP, National Asthma Education and Prevention Program.
*2007 NAEPP Expert Panel Report 3; †In children ≥ 12 years of age, > 2 days/week, but not daily, and more than 1 times on any day.