Comprehensive characterization of difficult-to-treat asthma reveals near absence of T2-low status

Hitasha Rupani, Mohammed Aref Kyyaly, Adnan Azim, Rana Abadalkareen, Anna Freeman, Paddy Dennison, Peter Howarth, Ratko Djukanovic, Pandurangan Vijayanand, Gregory Seumois, S Hasan Arshad, Hans Michael Haitchi, Ramesh J Kurukulaaratchy

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Asthma is conventionally stratified as type 2 inflammation (T2)-high or T2-low disease. Identifying T2 status has therapeutic implications for patient management, but a real-world understanding of this T2 paradigm in difficult-to-treat and severe asthma remains limited.

To identify the prevalence of T2-high status in difficult-to-treat asthma patients using a multicomponent definition and compare clinical and pathophysiologic characteristics between patients classified as T2-high and T2-low.

We evaluated 388 biologic-naive patients from the Wessex Asthma Cohort of difficult asthma (WATCH) study in the United Kingdom. Type 2–high asthma was defined as 20 parts per billion or greater FeNO , 150 cells/μL or greater peripheral blood eosinophils, the need for maintenance oral corticosteroids, and/or clinically allergy-driven asthma.

This multicomponent assessment identified T2-high asthma in 93% of patients (360 of 388). Body mass index, inhaled corticosteroid dose, asthma exacerbations, and common comorbidities did not differ by T2 status. Significantly worse airflow limitation was found in T2-high compared with T2-low patients (FEV1/FVC 65.9% vs 74.6%). Moreover, 75% of patients defined as having T2-low asthma had raised peripheral blood eosinophils within the preceding 10 years, which left only seven patients (1.8%) who had never had T2 signals. Incorporation of sputum eosinophilia 2% or greater into the multicomponent definition in a subset of 117 patients with induced sputum data similarly found that 96% (112 of 117) met criteria for T2-high asthma, 50% of whom (56 of 112) had sputum eosinophils 2% or greater.

Almost all patients with difficult-to-treat asthma have T2-high disease; less than 2% of patients never display T2-defining criteria. This highlights a need to assess T2 status comprehensively in clinical practice before labeling a patient with difficult-to-treat asthma as T2-low.
Original languageEnglish
Pages (from-to)2812-2821.e4
JournalJournal of Allergy and Clinical Immunology: In Practice
Issue number9
Publication statusPublished - 26 May 2023
Externally publishedYes

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