Heterogeneity of phenotypes in severe asthmatics. The Belgian Severe Asthma Registry (BSAR)

SummaryThe Belgian severe asthma registry is a web-based registry encompassing demographic, clinical, functional and inflammatory data of severe asthmatics (SA), aiming at improving awareness, knowledge on its natural history and subphenotypes, and offering tools to optimize care of this asthma population.MethodsThe cross-sectional analyses of this registry included 350 SA as defined by the ATS (2000) from 9 Belgian centres, with at least one year follow up.ResultsMean age was 55 ± 14 yrs. SA were more frequently female (57%) and atopic (70%). Late-onset asthma (≥40 yr) was observed in 31% of SA. Current smokers represented 12% while 31% were ex-smokers. In addition to high doses ICS + LABA, 65% of patients were receiving LTRA, 27% anti-IgE and 24% maintenance oral corticosteroids (8 mg (Interquartile range-IQR:4–8) methylprednisolone). Despite impaired airflow (median FEV1:67%; IQR: 52–81) only 65% had a post-bronchodilator FEV1/FVC ratio 1.5.ConclusionIn this cohort of patients with severe asthma, the majority displayed indices of persistent airflow limitation and eosinophilic inflammation despite high-dose corticosteroids, suggesting potential for eosinophil-targeted biotherapies.