A recently published multinational cohort study may be the largest to date that’s found the age of asthma onset is an integral factor in defining the severity of disease and the frequency of comorbidities.
“It’s very simple to ask your patient, ‘Did you have asthma as a child? When did your asthma start?’” coauthor Guy Brusselle, MD, a professor at the University of Ghent in Belgium, told Medscape Medical News in an interview. “You do not need expensive investigations, [computed tomography] (CT) scans or proteomics or genomics; just two simple questions.”
The retrospective cohort study, published in The Journal of Allergy and Clinical Immunology: In Practice, combined national electronic health records databases from five different countries—the United Kingdom, Spain, Italy, the Netherlands, and Denmark—that included 586,436 adult asthma patients. The study divided the patients into three subtypes: childhood-onset asthma, meaning a diagnosis before age 18 (n = 81,691); adult-onset disease, defined as a diagnosis between ages 18 and 40 (n = 218,184); and late-onset, defined as a diagnosis made after age 40 (n = 286,561).
Brusselle said the study found stark differences in characteristics between the three subtypes, including an increasing risk for women with later age of onset. Across the five databases, females comprised approximately 45% of those with childhood-onset asthma, but about 60% of those with later onset disease, Brusselle said.