Mild vedvarende astma defineres som astmasymptomer mere end en gang om ugen men mindre end en gang om dagen, natlige symptomer mere end to gange om måneden men mindre end en gang om ugen, normal lungefunktion mellem episoderne.
Mild persistent asthma is defined as asthma symptoms more than once a week but less that once a day, nocturnal symptoms more than twice a month but less than once a week, normal lung function between episodes.