Early Asthma, but Not Sensitization, Linked to Lung Function

TOPLINE:

Early-onset asthma was associated with impaired lung function at age 19 years, but contrary to researchers’ expectations, sensitization to aeroallergens did not appear to influence this outcome.

METHODOLOGY:

• Researchers analyzed data from 1495 participants in Sweden to assess factors associated with lung function at age 19 years.
• Participants completed questionnaires and underwent skin prick testing at ages 8, 12, and 19 years, and spirometry at age 19 years as part of the Obstructive Lung Disease in Northern Sweden research program.
• Participants were considered sensitized to aeroallergens if they had a mean wheal size of ≥ 3 mm 15 minutes after a skin prick test with any of the tested allergens, including pollen (birch, timothy, and mugwort), cat, dog, horse, mites, and molds.

TAKEAWAY:

• Participants with early-onset persistent asthma (ie, asthma at ages 8 and 19 years) had a lower forced expiratory volume in 1 second (FEV₁)/forced vital capacity (FVC) ratio than those without asthma (P < .001).
• Participants with early-onset asthma, including those whose asthma was in remission by age 19 years, had a significantly lower FEV₁ than those without asthma (P = .001).
• Maternal smoking during pregnancy was associated with lower lung function. However, aeroallergen sensitization — regardless of age at onset — showed no association with any measure of lung function, the researchers reported.

IN PRACTICE:

“As the association between asthma and impaired lung function is well established and allergen sensitization is a strong risk factor for asthma, we expected sensitization, particularly early onset, to negatively affect lung function,” the authors of the study wrote. “However, we did not find any association between aeroallergen sensitization and lung function.”

Features of asthma, rather than allergen sensitization, may determine lung impairment, they added.

SOURCE:

Eva Rönmark, PhD, Umeå University, Umeå, Sweden, was the corresponding author of the study, which was published online on July 23 in Clinical and Translational Allergy.

LIMITATIONS:

The relatively small number of patients with asthma in the study limited further analyses based on detailed phenotyping.

DISCLOSURES:

The study was supported by grants from sources such as the Swedish Heart‐Lung Foundation, the Swedish Asthma‐Allergy Foundation, and the Swedish Research Council. ALK‐Abelló, a pharmaceutical company, provided extracts for skin prick tests. The authors reported having no conflicts of interest.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.