Table. Severity classification for flare-ups (exacerbations)
|Mild||Worsening of asthma control that is only just outside the normal range of variation for the individual (documented when patient is well)||
More symptoms than usual, needing reliever more than usual (e.g. >3 times within a week for a person who normally needs their reliever less often), waking up with asthma, asthma is interfering with usual activities
A gradual reduction in PEF† over several days
Events that are (all of):
|More symptoms than usual, increasing difficulty breathing, waking often at night with asthma symptoms|
|Severe||Events that require urgent action by the patient (or carers) and health professionals to prevent a serious outcome such as hospitalisation or death from asthma||Needing reliever again within 3 hours, difficulty with normal activity|
† Applies to patients who monitor their asthma using a peak expiratory flow meter (single PEF measurements in clinic not recommended for assessing severity of flare-ups).
Note: the ATS/ERS Task Force recommended that severe exacerbations should be defined in clinical trials as the use of oral corticosteroids for 3 or more days. However, this definition is not applicable to clinical practice.
Source: Reddel H, Taylor D, Bateman E et al. An official American Thoracic Society/European Respiratory Society statement: asthma control and exacerbations: standardizing endpoints for clinical asthma trials and clinical practice. Am J Respir Crit Care Med 2009; 180: 59-99. Available at: http://www.thoracic.org/statements