Associations Between Social Determinants of Health and Adherence to Biologic Therapies in Patients with Severe Asthma: Real-World Evidence from a Large US Claims Analysis.

Abstract

Purpose: This study describes factors associated with biologic initiation and adherence, and impacts of adherence on exacerbations among US patients with severe asthma.

Patients and methods: This retrospective cohort study defined two populations, biologic-eligible patients and biologic users, using the Komodo Research Database of healthcare claims (2016-2024). The biologic-eligible cohort was defined as patients with severe asthma who had ≥2 exacerbations within 12 months, after the severe asthma index date. Severe asthma was defined as ≥3 month medium-to-high-dose inhaled corticosteroid use with ≥1 overlapping supply with controller therapy. The severe asthma index date was the first day of overlapping treatment supply. Biologic users were defined as patients with ≥2 dispensings of the same biologic and ≥2 asthma diagnoses in the year prior to biologic initiation. In the biologic-eligible cohort, biologic initiation was evaluated and compared between less- and more-favored social determinants of health (SDOH) areas (based on census-level quartiles). Adherence (assessed based on refills and treatment gaps) and exacerbations were assessed among biologic users in the 12 months following biologic initiation and compared between less- and more-favored SDOH areas.

Results: Overall 29,652 patients had ≥2 years of follow-up in the biologic-eligible cohort. Of these, 11.3% (n=3362) initiated biologics. In total, 16,336 patients were included in the biologic-user cohort, among whom 62.6% were adherent, 12.1% partially adherent, 3.1% minimally adherent, and 22.3% discontinued treatment. Biologic initiation and adherence were lower in less- versus more-favored SDOH areas. Compared with adherent patients, those who were partially/minimally adherent or discontinued treatment in the 12 months following biologic initiation had significantly more exacerbations post-landmark period (+18% overall and +28% hospitalization-defined exacerbations).

Conclusion: Disparities in biologic initiation and adherence exist between severe asthma populations with different characteristics and SDOH. Biologic adherence is associated with fewer exacerbations compared with partial adherence, minimal adherence, and treatment discontinuation.