Bronchial thermoplasty decreases airway smooth muscle mass in severe asthma

After bronchial thermoplasty, airway smooth muscle mass was significantly decreased after 6 months in adults with severe asthma, according to results of the TASMA trial.

“Observational studies have shown a reduction in airway smooth muscle mass after bronchial thermoplasty,” Annika W.M. Goorsenberg, with the department of respiratory medicine at Amsterdam UMC at the University of Amsterdam, and colleagues wrote in the American Journal of Respiratory and Critical Care Medicine.

Researchers conducted a randomized, multicenter trial that included 40 patients with severe asthma who were assigned to receive immediate bronchial thermoplasty (n = 20; mean age, 45 years; 85% women) or to a control group in which bronchial thermoplasty was delayed for 6 months (n = 20; mean age, 46 years; 60% women).

There was a more than 50% decrease in median airway smooth muscle mass in the immediate bronchial thermoplasty group compared with no change in the delayed group (P = .0004).

The immediate bronchial thermoplasty group had an improvement in asthma control of –0.79 in Asthma Control Questionnaire scores compared with 0.09 in the delayed group (P = .006). For health-related quality of life, in the immediate bronchial thermoplasty group, Asthma Quality of Life Questionnaire scores improved to 0.83 compared with –0.02 in the delayed group (P = .04).

In the total group, treatment response was positively associated with serum immunoglobulin E and eosinophils but not with baseline airway smooth muscle mass.

“These findings suggest that patients with high blood eosinophil counts and/or IgE levels are more likely to respond to bronchial thermoplasty treatment,” the researchers wrote.