Collected Dataset / DOORWAY_index

• Canada

Montreal, Quebec, Ottawa and London

• Moderate to severe asthma exacerbation

Participants were eligible if they: (1) were aged 1–17 years; (2) had asthma, defined as: (i) prior diagnosis of asthma made by a physician; (ii) prior documented episode of acute cough, wheezing and/or dyspnoea with significant response to inhaled β2-agonists or to oral corticosteroids; (iii) in a child aged <2 years, three or more episodes of cough, wheezing and/or dyspnoea, including the index visit or (iv) previous lung function tests showing significant reversibility postbronchodilation (≥12% FEV1 or ≥25% Rrs at 4–8 Hz) or a positive provocation test (PC20 ≤8 mg/mL or provocation dose (to increase Rrs by 50% or more (PD50) ≤8 mg/mL), in keeping with the American Thoracic Society and European Respiratory Society criteria; (3) presented with an acute episode of cough, wheezing and/or dyspnoea; (4) had moderate-to-severe airway obstruction, defined as a PRAM score >3 at baseline; (5) had a good understanding of English or French and (6) were accompanied by parents or legal guardians.

Patients were excluded if they presented: (1) with another chronic respiratory condition (such as bronchopulmonary dysplasia or cystic fibrosis); (2) with a reasonable suspicion of bronchiolitis or foreign body aspiration; (3) a history of hypersensitivity to salbutamol, ipratropium bromide or oral prednisolone; (4) a relative or absolute contraindication to receiving oral corticosteroids such as recent exposure to varicella or live vaccine in a susceptible child or (5) with confirmed or suspected pregnancy status.

• Specific population

• Other specific population :

  Children visiting emergency department with an asthma exacerbation.

From 975 enrolled patients:

Patients provided DNA samples: 906 samples

Patients provided Cotinine samples: 930 samples

Patients provided nasopharyngeal samples: 968 samples

Patients provided sputum samples: 11 samples