Asthma is a heterogeneous and complex condition characterized by chronic airway
inflammation, which may be clinically stratified into three main phenotypes: type 2 (T2) low, T2-high allergic, and T2-high non-allergic
asthma. This real-world study investigated whether phenotyping patients with
asthma using non-invasive parameters could be feasible to characterize the T2-low and T2-high
asthma phenotypes in clinical practice. This cross-sectional observational study involved asthmatic outpatients (n = 503) referring to the Severe
Asthma Centre of the San Luigi Gonzaga University Hospital. Participants were stratified according to the patterns of T2
inflammation and atopic sensitization. Among outpatients, 98 (19.5%) patients had T2-low
asthma, 127 (25.2%) T2-high non-allergic, and 278 (55.3%) had T2-high allergic phenotype. In comparison to T2-low, allergic patients were younger (OR 0.945, p < 0.001) and thinner (OR 0.913, p < 0.001), had lower
smoke exposure (OR 0.975, p < 0.001) and RV/TLC% (OR 0.950, p < 0.001), higher prevalence of
asthma severity grade 5 (OR 2.236, p < 0.05), more frequent
rhinitis (OR 3.491, p < 0.001) and chronic
rhinosinusitis with (OR 2.650, p < 0.001) or without (OR 1.919, p < 0.05)
nasal polyps, but less common arterial
hypertension (OR 0.331, p < 0.001). T2-high non-allergic patients had intermediate characteristics. Non-invasive phenotyping of asthmatic patients is possible in clinical practice. Identifying characteristics in the three main
asthma phenotypes could pave the way for further investigations on useful
biomarkers for
precision medicine.