Real-world characterization of severe asthma in Greece: Results from the Greek Severe Asthma Registry (GSAR)

Background Severe asthma (SA) imposes a disproportionate burden on patients and healthcare systems worldwide, yet region-specific data from Southern Europe remain scarce. The Greek Severe Asthma Registry (GSAR), an initiative of the Hellenic Thoracic Society, provides the first nationwide characterization of SA in Greece. Methods We analyzed cross-sectionally data from 619 adult patients (median age: 56 years; 61.1% female) with SA, recruited across 13 specialized hospital centers and 11 private respiratory practices between March 2018 and November 2021. Patients were stratified by age of asthma onset, biologic therapy use, and maintenance oral corticosteroid (mOCS) dependence. Clinical, inflammatory, and treatment characteristics were assessed, alongside exacerbation predictors. Results The study population exhibited substantial disease burden, with 434 patients (70.1%) experiencing ≥1 exacerbation and 149 (24.1%) requiring hospitalization in the prior year. Late onset asthma (60.7%) was associated with a faster progression to severe disease, higher exacerbation risk (79.8% versus 69.5%, p=0.004), and more frequent cardiometabolic comorbidities versus early onset asthma. Despite better asthma control (Asthma Control Test [ACT] ≥20: 61.8% versus 50.5%, p=0.012), biologically treated patients (57%) had more severe disease, including lower FEV 1 predicted (73% versus 81%, p<0.001). Patients receiving mOCS (18.9%) exhibited poorer asthma control, higher exacerbation rates, and more frequent corticosteroid-related comorbidities. In multivariable models, elevated blood eosinophil count (Incidence Rate Ratio [IRR]: 1.044 per 100 cells/μL) and reduced FEV 1 % (Odds Ratio [OR]: 0.97 per 1% increase) were independent predictors of exacerbations. Conclusions This study highlights the phenotypic heterogeneity of SA in Greece and reveals region-specific treatment patterns and unmet clinical needs despite access to advanced therapies. These real-world findings may guide national asthma care strategies and contribute to European initiatives aimed at optimizing asthma management.