Bronchial remodeling-based latent class analysis predicts exacerbations in severe preschool wheezers

Abstract

<b>Background:</b> The heterogeneity of the preschool wheezers population may be related to different patterns of inflammation, obstruction and/or bronchial remodeling. We hypothesized that assessing bronchial remodeling in severe preschool wheezers will be of help to clinicians by better characterizing the patient’s disease. <b>Aims and Objectives:</b> To identify bronchial remodeling-based latent classes of severe preschool wheezers, to compare clinical and biological data between classes and to assess the safety of bronchoscopy in such children. <b>Methods:</b> This double-center prospective study (NCT02806466) included severe preschool wheezers (1-5 years old), requiring fiberoptic bronchoscopy. Bronchial remodeling parameters (i.e., epithelial shedding, reticular basement membrane (RBM) thickness, mucus gland, fibrosis and bronchial smooth muscle (BSM) areas, density of blood vessels and RBM-BSM distance) were assessed and included in a latent class analysis to identify underlying unobserved classes. <b>Results:</b> Bronchoscopy was performed in 56 patients, 52 of which had analyzable biopsies. Two categories were identified: Compared to Class 2, Class 1 was characterized by increased RBM thickness, normalized BSM area, density of blood vessels, and, decreased mucus gland area, fibrosis and RBM-BSM distance. Class 1 was associated with increased cumulative number of exacerbations and percentage of &gt;3 exacerbation-prone patients during the year following bronchoscopy. No major side effects of the bronchoscopic procedure were noted. <b>Conclusion:</b> Assessing bronchial remodeling is clinically useful to identify severe preschool wheezers at risk of asthma exacerbations with a favorable benefit to risk ratio.