Initial maintenance therapy adherence among older adults with asthma-COPD overlap

OBJECTIVES: To examine the impact of initial maintenance therapy (IMT) type (inhaled corticosteroid [ICS] vs fixed-dose combination of ICS and long-acting β agonist [ICS/LABA]) on trajectories of adherence among older adults (≥65 years) with coexisting asthma and chronic obstructive pulmonary disease (COPD), known as asthma-COPD overlap (ACO). STUDY DESIGN: We used a longitudinal, retrospective cohort design. METHODS: This study used a cohort of older adults with ACO using longitudinal data from a 10% sample of Optum’s Deidentified Clinformatics Data Mart. We adopted group-based trajectory modeling to identify medication adherence trajectories over 12 months. Multinomial logistic regressions were used to evaluate the unadjusted and adjusted associations of IMT medication and adherence trajectory categories. All analyses accounted for treatment option selection bias with inverse probability treatment weighting. RESULTS: Of 1555 individuals, 73% of the sample used ICS/LABA for IMT. Four medication adherence trajectories were observed regardless of regimen: (1) persistent high adherence (12.0%), (2) progression to high adherence (20.8%), (3) progression to low adherence (10.5%), and (4) persistent low adherence (56.7%). Those who were initiated on ICS/LABA were less likely to have persistent low adherence (unadjusted odds ratio [OR], 0.44; 95% CI, 0.29-0.67) compared with those initiated on ICS monotherapy when “persistent high adherence” was used as the reference group. The relationship remained significant in adjusted regressions (adjusted OR, 0.38; 95% CI, 0.24-0.59). CONCLUSIONS: Real-world evidence suggests that using ICS/LABA for IMT may decrease the likelihood of persistent low adherence over time among older adults with ACO compared with ICS monotherapy.