Classification of severity of asthma

In clinic, This question always threw by physician to us. Most of us unable to answer it. I went through most of the standard textbook include Kumar and clerk, davidson,nichollas talley etc..in which none of the book mention about it..i would like to share this to those who are interested.

Category 1- Mild intermittent.....
Daytime symptoms less than once a week
Nocturnal symptoms less than once a month
Normal lung function

Category 2- Mild persistent......
Daytime symptoms more than once a week (but <1 per day)
Nocturnal symptoms more than twice a month
PEFR / FEV1 > 80%


Category 3- Moderate persistent....
Daytime symptoms daily
Nocturnal symptoms more than once a week
PEFR / FEV1 60 – 80%

Category 4- Severe persistent....
Daytime symptoms daily
Daily nocturnal symptoms
PEFR / FEV1 < 60%

I hope this is useful to all of you. However, some also argue that for category 1-daily symptom is less than twice /week and nocturnal symptom is less than twice /month. Here, I invites further discussion from all of you...Thanks.

A good undergraduate student reads beyond usual text books

There are four categories (determining STEPs of management) of asthma, as shown in the attachment. This is the most commonly used classification of severity.

Attachment: Bronchial Asthma Classifications.pdf

However, there is another widely used and arguably 'better' classification by GINA (The Global Initiative For Asthma). It classifies asthma control as:

1. Controlled
2. Partially Controlled
3. Uncontrolled

Regarding your doubt on whether Category 1 is symptoms less than once or twice per week, it is not that much important while managing an individual patient. You may remember and use <2 per week, as that is more practical.

A useful link: http://www.asthmacontrol.com/