ToAST:Investigating the Effect of Bronchial Thermoplasty on Cough in Patients With Severe Asthma

ToAST is designed as a two-visit observational study. During visit 1, written consent and measurements of baseline asthma characteristics were completed; history and examination, questionnaires (Asthma Control Questionnaires and Leicester Cough Questionnaire, and basic lung physiological assessment were performed. At the end of visit 1, a cough monitor was attached to the subject to monitor cough frequency for the next 24 hours and this was returned at visit 2. Visit 2 followed within two weeks after visit 1, during which a full dose capsaicin cough challenge was performed. Emergency contact details were given towards end of visit 2 should any adverse events occur. Telephone call within 48 hours, Day 3 and Day 7: The purpose of these phone calls was to ensure that the patient had not developed any adverse effects to the capsaicin challenge.