Differences in patient characteristics by age of asthma onset
Published: April 7, 2022
Asthma is characterized by chronic airway inflammation and frequently associated with other conditions (i.e. comorbidities). Asthma is a common condition where approximately 5 adults in 100 are affected. It can present according to multiple phenotypes which by themselves are important in asthma management and therapy. One of these asthma phenotypes is the age of first manifestation of asthma, which is defined as “childhood-onset” (starting before the age of 18 years), “adult-onset” (onset between 18 and 40 years old) and “late-onset” asthma (starting after the age of 40 years). Differences in comorbidities by age of asthma onset have been reported. However, most of these studies had modest sample sizes, were restricted to one single country, and did not differentiate between adult-onset and late-onset asthma.
In this recent article by Verhamme et al published in The Journal of Allergy and Clinical Immunology: In Practice, the authors describe the results of a large retrospective cohort study using data of patients with doctor diagnosed asthma from 5 European electronic health care record databases in the study period 2008-2013. In patients with asthma selected from these databases, the age at asthma onset was assessed, and patients were categorized into childhood-onset, adult-onset, and late-onset asthma. Next, characteristics in terms of comorbidities within these different phenotype classes were compared by estimating age-adjusted odds ratios.
In total, almost 600,000 patients with asthma were included, of whom 14% had childhood-onset asthma, 37% belonged to the adult-onset asthma category, and 49% belonged to the late-onset asthma category. Patients with late-onset asthma were more at risk of uncontrolled asthma (i.e. experiencing asthma exacerbations). Differences in patient characteristics were observed where patients with adult-onset asthma had a higher risk of overweight/obesity but lower risk of atopy compared to subjects with childhood-onset asthma. In contrast, patients with late-onset asthma compared to adult-onset asthma had a higher risk for nasal polyposis, overweight/obesity, reflux disease, and diabetes. The age of asthma onset should be considered when assessing asthma patients as it helps to phenotype asthma. Moreover, asthma management should not only focus on the control of respiratory symptoms, but should also include assessment and treatment of underlying comorbidities, which may differ by age of asthma onset.
The Journal of Allergy and Clinical Immunology: In Practice is an official journal of the AAAAI, focusing on practical information for the practicing clinician.