What does the trigger of new-onset asthma tell the clinician?
Published online: September 18, 2018
Asthma is a heterogeneous disease and affects people across all ages. Although asthma often develops during childhood, it can also develop during adulthood. This subtype of asthma is, in contrast to childhood-onset asthma, not associated with genetic predisposition but often seems to be incited by a specific trigger such as smoking, aspirin use, or occupational agents. Up until now it is not known whether the triggers of asthma-onset in adulthood are related to specific characteristics and if these triggers are related to asthma prognosis.
In a recently published article in The Journal of Allergy and Clinical Immunology: In Practice, Coumou and colleagues have examined the association between triggers of asthma onset in adulthood and clinical, functional, and inflammatory characteristics. Furthermore, they examined the relation between triggers of asthma onset and asthma remission, defined by no symptoms for > 1 year and no medication for > 1 year, after 5 years. This was done in a prospective cohort study including 200 adults with recently diagnosed asthma. The trigger of asthma onset was patient reported and defined by the question “What, in your opinion, elicited your asthma?” Patients’ characteristics and remission rate were compared amongst the 5 most reported triggers.
The authors identified 10 categories of onset triggers (ranking based on frequency of report): “no trigger identified” (38%), “upper respiratory tract symptoms” (22%), “new allergic sensitization” (11%), “pneumonia” (8%), “stressful life event” (7%), “other”(6%), “occupational exposure” (3%), “smoking cessation”(3%), “post-menopausal”(2%), and “aspirin use” (1%). When comparing patients’ characteristics between the 5 most reported triggers, a difference in clinical and inflammatory characteristics and remission rates was observed. “New allergic sensitization” was associated with mild atopic asthma and a relatively young age of asthma onset. “Pneumonia” was associated with previous smoking, low IgE levels with the highest remission rates (one third). Patients with “upper respiratory symptoms” had high markers of Type 2 inflammation (increased blood or sputum eosinophils, or elevated exhaled nitric oxide levels) and low disease remission rates. “No trigger identified” was not associated with any specific characteristic. Lastly, “stressful life event” was associated with high asthma medication usage, low Type 2 inflammation markers, and no disease remission.
This study by Coumou and colleagues shows that adults with new-onset asthma can be characterized based on the trigger that seemingly incited their asthma. Characteristics of these patients may fit with well described adult asthma phenotypes. The results of this study emphasize that the trigger of asthma onset is an important item in the medical history of adults with suspected new-onset asthma as it might hint towards underlying mechanisms and provide information on disease prognosis.
The Journal of Allergy and Clinical Immunology: In Practice is an official journal of the AAAAI, focusing on practical information for the practicing clinician.
New-onset asthma in adults; what does the trigger history tell us?
By Hanneke Coumou, Guus A. Westerhof, Selma B. de Nijs, Marijke Amelink, Elisabeth H. Bel