Tiotropium treatment for bronchiectasis: a randomised, placebo-controlled, crossover trial

Tiotropium via the HandiHaler device is an established long-acting, anticholinergic bronchodilator that prevents exacerbations and improves lung function in patients with chronic obstructive pulmonary disease. We hypothesised that tiotropium would reduce pulmonary exacerbations and improve lung function in patients with stable bronchiectasis and airflow limitation, and assessed the effect of tiotropium on these outcomes.

In a randomised, double-blind, two-period crossover trial, we recruited adult patients from three hospitals in New Zealand. Patients were excluded if they had a smoking history of >20 pack-years. Patients were assigned to either the tiotropium-placebo or placebo-tiotropium sequence in a 1:1 ratio, using randomly permuted blocks stratified by centre. Participants and investigators were masked to treatment allocation. Eligible patients received tiotropium 18 μg via HandiHaler daily for 6 months followed by 6 months of placebo, or vice versa, with a washout period of 4 weeks. The primary end-point was rate of event-based exacerbations during the 6-month period. Primary analyses were carried out in an intention-to-treat set.

90 patients were randomly assigned and 85 completed both treatment cycles. The rate of exacerbations was 2.17 per year under the tiotropium treatment and 2.27 per year under placebo (rate ratio 0.96, 95% CI 0.72-1.27; p=0.77). Tiotropium, compared with placebo, improved forced expiratory volume in 1 s by 58 mL (95% CI 23-92 mL; p=0.002). Adverse events were similar under both treatments.

Tiotropium via HandiHaler over 6 months significantly improved lung function but not frequency of exacerbations. Further research is required to understand the clinical context and significance of these findings.