We see many adult patients with asthma, but often times we are seeing patients that have been previously diagnosed with asthma during childhood and carry this diagnosis into adult life and are receiving treatment. It is not uncommon to see a patient having a symptom such as cough, which they felt was due to their asthma but which is not responding to therapy. For some of these patients it is often necessary to confirm the diagnosis of asthma with a special breathing test called methacholine challenge.
I recently came across some interesting information about the over- diagnosis of asthma in children. In the 1980’s it was felt that asthma was underdiagnosed and undertreated, and still is in some poor urban areas. However, the diagnosis of asthma more than doubled in the next 10-15 years. The diagnosis was often made on what we call a clinical basis, i.e. without testing. Various studies between 1996 and 2016 have indicated that the percent of over- diagnosis in children ranged from 54 percent to 90 percent, particularly if the only symptom initially was cough.
What do these findings mean for the adult population? If you have been told you have asthma as a child, but did not have this confirmed as an adult with special pulmonary testing, you may be receiving treatment that is unnecessary. Asthma medications are not without side effects, especially with long term use. There is increasing evidence that a large fraction of patients diagnosed with asthma do not have it.