Patients with uncontrolled asthma despite high doses of inhaled corticosteroid therapy plus another controller are defined as severe asthmatics. Tiotropium bromide respimat (TBR) is the only long-acting muscarinic antagonist (LAMA) approved for severe asthma. This study aimed to explore the frequency of severe asthmatics treated with TBR and characterize their clinical features in a real-life, registry-based setting. Baseline data from the Severe Asthma Network in Italy (SANI) registry have been analyzed to determine the use of TBR and other LAMA and compare clinical, functional, and inflammatory features associated with using LAMA.
Among a total of 698 enrolled patients, 35.9% were treated with LAMA (23.3% TBR, 4.5% tiotropium bromide handihaler, 4.5% aclidinium, 3.4% glycopyrronium bromide 0.3% umeclidinium bromide). Age of asthma onset was higher in patients taking LAMA, who, compared to others, were more frequently former smokers. They also had a higher annual exacerbation rate, experienced worst asthma control, worst disease-related quality of life, and poorer lung function. Bronchiectasis was more frequently found in LAMA users (25.9% vs. 13.1%).
TBR is still underused in severe asthma in a real-life setting, while a relevant proportion of patients are treated with other LAMA that is not approved for severe asthma treatment. Patients taking LAMA have features characteristic of even more severe asthma.