Who gets severe asthma?
We don’t know exactly why some people develop severe asthma; but it is likely to be caused by several factors. Asthma is more likely to become severe in people with asthma who are older, or who are smokers. Sometimes asthma becomes more severe after a respiratory infection. Sometimes the reason is not known.
The cause of asthma is currently unknown but there are several risk factors including respiratory viruses in childhood, allergies (e.g. eczema and hay fever), exposure to tobacco smoke or pollution, diet, and a family history of asthma or infection. The effect of these factors on the development of severe asthma however is still not fully understood.