Asthma Classification

Asthma is clinically classified according to the frequency of symptoms, FEV1 and peak expiratory flow rate.[6] Asthma may also be classified as atopic (extrinsic) or non-atopic (intrinsic), based on whether symptoms are precipitated by allergens (atopic) or not (non-atopic).

	Symptoms	Night Symptoms	%FEV1 of Predicted	FEV Variability
Intermittent	more than 1 per week	more than 2 per month	less than 80%	more than 20%
Mild persistent	less than 1 per week but more than 1 per day	less than 2 per month	less than 80%	20–30%
Moderate persistent	Daily	less than 1 per week	60–80%	less than 30%
Severe persistent	Daily	Frequent	more than 60%	less than 30%

Main Article: Lung Disease: Asthma