Adding tiotropium or long-acting β2-agonists to inhaled corticosteroids: Asthma-related exacerbation risk and healthcare resource utilization

Background:

Based on current clinical guidelines, long-acting β2-agonists (LABA) are frequently prescribed before long-acting muscarinic antagonists (LAMA) as an add-on to inhaled corticosteroids (ICS) in uncontrolled asthma. However, there is insufficient real-world evidence that supports this therapeutic approach.

Objective:

The objective was to compare asthma exacerbations and healthcare resource utilization in patients with asthma using the LAMA tiotropium bromide (Tio) or a LABA as an add-on to ICS (ICS + Tio or ICS/LABA) in a real-world setting.

Methods:

This retrospective, observational study included patients aged ≥12 years with asthma diagnoses identified in a U.S. longitudinal claims database (October 2015 to August 2020). The ICS + Tio and ICS/LABA cohorts were 1:2 propensity score matched for baseline variables. Outcomes were compared in the postmatched cohorts, and the risk of exacerbation was evaluated by using Kaplan-Meier curves.

Results:

After propensity score matching, there were 633 and 1266 patients in the ICS + Tio and ICS/LABA cohorts, respectively. The proportion of patients who experienced a severe or a moderate-or-severe exacerbation during follow-up was similar between the ICS + Tio versus ICS/LABA cohorts (4% versus 3%, p = 0.472, and 50% versus 45%, p = 0.050, respectively). The mean time to first severe (ICS + Tio 43.8 days versus ICS/LABA 49.4 days, p = 0.758) and moderate-or-severe exacerbation (ICS + Tio 65.8 days versus ICS/LABA 58.9 days, p = 0.474) was not statistically different between cohorts. The treatments had no effect on the risk of severe exacerbation, although it was 36% lower in ICS + Tio users than in ICS/LABA users (hazard ratio 0.64 [95% confidence interval, 0.22‐1.84]). All-cause and asthma-related average monthly healthcare resource utilization were comparable between the treatments for hospitalizations and emergency department visits but were significantly greater in the ICS + Tio cohort than in the ICS/LABA cohort for asthma-related outpatient visits (p < 0.0001).

Conclusion:

This study provides real-world evidence that ICS + Tio may be a valid alternative when ICS/LABA cannot be used as first-line treatment for asthma maintenance therapy.