ToAST; Investigating the effects of bronchial thermoplasty on cough
Research type
Research Study
Full title
Investigating the effects of bronchial thermoplasty (BT) on cough responses in patients with severe asthma\n\n
IRAS ID
200251
Contact name
Jacky Smith
Contact email
Duration of Study in the UK
1 years, 0 months, 0 days
Research summary
Asthma affects an estimated 300 million people worldwide and is characterised by airway inflammation, hyper-responsiveness (AHR) and reversible airflow limitation associated with symptoms of wheeze, cough, chest tightness and breathlessness. The mechanism and relationship between airway inflammation, AHR and developing symptoms is unknown. The role of airway nerves in the development of asthma is unclear and under-studied. As coughing is controlled by an airway reflex, the study of cough can provide insights into the role of nerve function. Bronchial thermoplasty (BT) is a new asthma treatment which uses short pulses of radiofrequency heat to reduce smooth muscle thickness to prevent airway narrowing. Studies have shown this technique can reduce the number of asthma attacks. However, it is unclear whether the process of performing BT affects the nerves which are present in the wall of the airways. \nOur study therefore primarily aims to assess the safety and feasibility of capsaicin challenge in subjects with severe asthma and to also investigate the effects of BT in subjects who have had the treatment with those who have not. We predict that subjects who have BT demonstrate reduced responses to inhaled capsaicin. Furthermore inhaling capsaicin will not reduce lung function by more than 10%.\nThis is a follow up from a study which found capsaicin evoked cough responses were heightened and more sensitive in patients mild asthma compared with healthy volunteers(13/NW/0043 and 13/NW/0040). \n\nIn this study we aim to recruit 24 people with severe asthma, of which 12 have already had BT treatment in the past, to attend 2 study visits at Wythenshawe Hospital. Study visits will involve a blood test, 24hr cough monitoring and a capsaicin challenge, which are described in detail in the participant information sheet.
REC name
North West - Preston Research Ethics Committee
REC reference
16/NW/0210
Date of REC Opinion
6 Jun 2016
REC opinion
Further Information Favourable Opinion