Real-world patterns and implications of short-acting β2-agonist use in patients with asthma in the United States

Abstract

Background: Short-acting β₂-agonist (SABA) use is one measure reflecting asthma control.

Objective: To evaluate the associations between real-world SABA use and severe asthma exacerbations in the United States.

Methods: Patients with asthma 12 years of age or older receiving SABA in the IBM MarketScan research databases of US administrative claims from September 30, 2014, to September 30, 2016, were evaluated. Patients with 12 months' continuous eligibility before and after their first SABA claim (index SABA), an asthma diagnosis before through 60 days postindex, and either one additional SABA or at least 1 maintenance fill(s) were included. SABA claims postindex (including index fill) were grouped as follows: low: index only; medium: 2 to 3 canisters per year; and high: 4 or more canisters per year. Differences in SABA exposure with respect to disease severity groups and severe asthma exacerbations (hospitalizations, emergency visits, or outpatient systemic corticosteroids) were analyzed by analysis of variance and χ² (significance, P ≤ .05).

Results: A total of 135,540 patients were included: 62.8% women; mean (SD) age, 40.9 (18.3) years; SABA fills per 12-months postindex: 3.0(2.7). Furthermore, 28% of patients filled 1 SABA, 47% 2 to 3, and 25% 4 or more canisters per year. Despite higher maintenance medication possession ratio with increasing SABA (low, 0.53 (0.37); medium, 0.59 (0.35); high, 0.66 (0.32)), annual exacerbation rate per person per year and percent of patients within each SABA group having at least 1 exacerbation rose as SABA fills increased (low, 1.00 (1.45), 45.8%; medium, 1.20 (1.62), 54.3%; high, 1.50 (1.94), 58.7%). Mean SABA fills differed between patients with 0 exacerbation, 2.8 (2.6); 1 exacerbation, 2.9 (2.5); and 2 or more exacerbations, 3.3 (2.9).

Conclusion: Exacerbation risk increased with increasing SABA fills. Management strategies ensuring adequate anti-inflammatory therapy delivered to the airways when symptoms occur may be needed to mitigate asthma morbidity.