Abstract
Introduction/Background: Biomarker-defined clusters of severe asthma patients were previously identified via hierarchical cluster analysis; a cluster of older females with low-to-medium Type 2 (T2) biomarkers was characterized (Denton, E. et al. J Allergy Clin Immunol Pract 2021;9:2680-8.e7).
Aims and Objectives: To describe biomarker-defined clusters (blood eosinophil counts [BEC], FeNO, and serum IgE [IgE]) in severe asthma patients, and characterize T2-low asthma using a model-based approach to clustering.
Methods: Patients in the International Severe Asthma Registry (ISAR) with biomarker data were included, regardless of biologic use. A Gaussian finite mixture model was used to perform cluster analyses using BEC, FeNO and IgE standardized by z score. The prespecified thresholds for low biomarkers were BEC <300cells/µL, FeNO <25ppb and IgE <75 IU/mL.
Results: Of 4459 patients, five clusters were identified. Cluster 1 had females with low T2 biomarkers. Cluster 2 had high BEC and FeNO; Cluster 3, triple T2 biomarker high; Cluster 4, high BEC; Cluster 5, high IgE.
Figure: Median (IQR) biomarker levels and characteristics of clusters
Conclusions: In line with previous findings, a cluster with females and low biomarkers suggested low T2 involvement. The other 4 clusters varied in biomarker elevations, highlighting the complexity of T2 inflammatory involvement in severe asthma.
Footnotes
Cite this article as Eur Respir J 2022; 60: Suppl. 66, 2814.
This article was presented at the 2022 ERS International Congress, in session “-”.
This is an ERS International Congress abstract. No full-text version is available. Further material to accompany this abstract may be available at www.ers-education.org (ERS member access only).
- Copyright ©the authors 2022
