Available online 21 September 2022

What is already known about this topic?

Different studies have shown that mucus plugging in asthma is associated with worse spirometry, greater type 2 inflammation and more frequent severe exacerbations.

What does this article add to our knowledge?

Here we determine clinical associations with mucus plugging in moderate-to-severe asthma in the same study.

How does this study impact current management guidelines?

Mucus plugging should be included as an important aspect of routine severe asthma workup for tailoring biologic decisions.

Mucus plugging (MP) is recognised as a contributory factor to airway obstruction and symptoms in persistent asthma.

We aimed to determine phenotypic associations of mucus plugging in patients with moderate-to-severe asthma in a real-life clinic setting.

MPs were identified by a thoracic radiologist on high resolution CT imaging. A MP score was subsequently calculated and analysed along with type 2 (T2) biomarkers, spirometry, severe exacerbations and asthma control for 126 moderate to severe asthma patients prior to biologic therapy.

Asthma patients with MP had significantly worse FEV1%, FEF25-75% and FEV1/FVC; higher levels of peripheral blood eosinophils, fractional exhaled nitric oxide, total IgE and A. fumigatus IgE titres; and experienced more frequent prior severe exacerbations. FEV1/FVC, ≥2 exacerbations/yr, blood eosinophils, total IgE and A. fumigatus IgE titres were associated with MP after adjusting for confounders.

Poorly controlled asthma patients with MP exhibited significantly worse airflow obstruction, greater T2 inflammation associated with more frequent severe exacerbations. Impaired spirometry, more frequent exacerbations, raised blood eosinophils, total IgE and A. fumigatus IgE increased the likelihood of MP.

mucus plugging

asthma

eosinophils

type 2 inflammation

airway obstruction

exacerbations

allergic bronchopulmonary aspergillosis

Asthma Control Questionnaire

American Thoracic Society

European Respiratory Society

fractional exhaled nitric oxide

forced expiratory volume in 1 second

high resolution computed tomography

inhaled corticosteroids

long-acting beta-agonist

long-acting muscarinic-antagonist

leukotriene receptor antagonist

peripheral blood eosinophils

© 2022 Published by Elsevier Inc. on behalf of the American Academy of Allergy, Asthma & Immunology