Heat: the new treatment for asthma?
Asthma sufferers may breathe easier thanks to a new treatment being evaluated by an international consortium of researchers, including Dr. Ronald Olivenstein, McGill University Health Centre Asthma Clinic Director. Their multi-centre clinical study, the Asthma Intervention Research (AIR) trial, involves using thermal energy (heat) to treat asthmatic airways — referred to as bronchial thermoplasty. Their findings, published today in the New England Journal of Medicine, show promising results for patients with moderately severe to severe asthma. This study is part of a global clinical trial to examine the efficacy and safety of this technique, led by Dr. Michel Laviolette of the University of Laval as senior author.
"We saw improved asthma control following bronchial thermoplasty,” says Dr. Olivenstein, a McGill assistant professor of medicine. “This technique provides for the first time, a non-medicinal treatment option.”
The bronchial thermoplasty patients showed the following positive findings in comparison with patients not treated with the procedure:
- reduced rate of asthma exacerbation per year;
- increased number of days per year without asthma symptoms;
- improved quality of life;
- decreased amount of rescue medication (short acting bronchodilators) required per day — improved overall control of asthma.
Medication is currently the traditional treatment available for asthma sufferers. Bronchial thermoplasty is an outpatient procedure performed under light sedation and involves insertion of a catheter with a thermal tip into the airways of the lung that allows for application of the thermal energy at various points within the airway. Currently, three such procedures are required to completely treat the airways. Each treatment takes 30 to 45 minutes and patients return home the same day and are able to resume normal activities.
Researchers from Canada, Denmark, Britain, and Brazil evaluated 112 asthma patients. Half were treated only with traditional asthma drugs and half were treated with bronchial thermoplasty in addition to the asthma drugs. Thermoplasty patients showed more improvement in the overall control of asthma than those receiving inhaled medication.
Asthma is a common disease in which the airways in the lung become inflamed in response to an asthma trigger, such as an allergen or irritant. Excess mucus is produced and the muscles in the airway walls may contract and narrow, leading to breathing difficulties. Asthma affects over 2.7 million Canadians and causes over 500 deaths each year in Canada and is increasing globally.
This study was financed by Asthmatx Inc., developers of the Alair Bronchial Thermoplasty system. Dr. Olivenstein and other members of this team have no financial interest in Asthmatx Inc.