title: Heterogeneity of phenotypes in severe asthmatics. The Belgian Severe Asthma Registry (BSAR).
abstract: The 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.
  
  
  METHODS
  The 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.
  
  
  RESULTS
  Mean 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 <70%. The median blood eosinophil count was 240/mm³. The median FENO was 26 ppb (IQR: 15-43) and 22% of SA had FENO ≥ 50 ppb. Induced sputum was successful in 86 patients. Eosinophilic asthma (sputum Eos ≥ 3%) was the predominant phenotype (55%) while neutrophilic (sputum Neu ≥ 76%) and paucigranulocytic asthma accounted for 22% and 17% respectively. Comorbidities included rhinitis and chronic rhinosinusitis (49%), nasal polyposis (19%), oesophageal reflux (36%), overweight and obesity (47%) and depression (19%). In addition, 8% had aspirin-induced asthma and 3% ABPA. Asthma was not well-controlled in 83% according to ACT < 20 and 77% with ACQ > 1.5.
  
  
  CONCLUSIONS
  In 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.
authors.affiliation: Department of Pulmonary Medicine, CHU Sart-Tilman, Liege, I³GIGA Research Group, University of Liege, Belgium. Electronic address: fschleich@chu.ulg.ac.be.
authors.forename: F
authors.initials: F
authors.lastname: Schleich
authors.affiliation: Department of Respiratory Medicine, Ghent University Hospital, Belgium.
authors.forename: G
authors.initials: G
authors.lastname: Brusselle
authors.affiliation: Department of Pulmonary Medicine, CHU Sart-Tilman, Liege, I³GIGA Research Group, University of Liege, Belgium.
authors.forename: R
authors.initials: R
authors.lastname: Louis
authors.affiliation: Department of Respiratory Medicine, CHU of Mont-Godinne, Université Catholique de Louvain, Yvoir, Belgium.
authors.forename: O
authors.initials: O
authors.lastname: Vandenplas
authors.affiliation: Chest Department, Erasme University Hospital, Université Libre de Bruxelles, Brussels, Belgium.
authors.forename: A
authors.initials: A
authors.lastname: Michils
authors.affiliation: Laboratory of Allergy & Mucosal Immunology and Cliniques Universitaires St-Luc, Université Catholique de Louvain (UCL), Brussels, Belgium.
authors.forename: C
authors.initials: C
authors.lastname: Pilette
authors.affiliation: Department of Respiratory Medicine, CHU-Charleroi, A. Vésale Hospital, Charleroi, Belgium.
authors.forename: R
authors.initials: R
authors.lastname: Peche
authors.affiliation: Department of Pulmonary Medicine, CHU Sart-Tilman, Liege, I³GIGA Research Group, University of Liege, Belgium.
authors.forename: M
authors.initials: M
authors.lastname: Manise
authors.affiliation: Department of Respiratory Medicine, Ghent University Hospital, Belgium.
authors.forename: G
authors.initials: G
authors.lastname: Joos
mesh_terms: D058665:Adrenergic beta-1 Receptor Agonists / Q000627:therapeutic use; D000328:Adult; D000368:Aged; D001249:Asthma / Q000097:blood / Q000188:drug therapy* / Q000453:epidemiology* / Q000503:physiopathology; D001530:Belgium / Q000453:epidemiology; D015897:Comorbidity; D003430:Cross-Sectional Studies; D004522:Educational Status; D004651:Employment / Q000706:statistics & numerical data; D004804:Eosinophils / Q000473:pathology; D005260:Female; D005541:Forced Expiratory Volume / Q000502:physiology; D005938:Glucocorticoids / Q000627:therapeutic use; D006760:Hospitalization / Q000706:statistics & numerical data; D006801:Humans; D007958:Leukocyte Count; D008297:Male; D008875:Middle Aged; D010641:Phenotype; D011788:Quality of Life; D012042:Registries; D014797:Vital Capacity / Q000502:physiology
chemical_list: D058665:Adrenergic beta-1 Receptor Agonists; D005938:Glucocorticoids
keywords: Comorbidities; Inflammation; Phenotype; Severe asthma