Abstract
IMPORTANCE: High out-of-pocket costs and improper use of maintenance inhalers contribute to poor outcomes among patients with chronic obstructive pulmonary disease (COPD). There is limited evidence for how addressing these barriers could improve adherence and affect COPD exacerbations, spending, or racial disparities in these outcomes. OBJECTIVE: To examine the effect of a national program to reduce beneficiary cost sharing for COPD maintenance inhalers and provide medication management services that included education on proper technique for inhaler use. DESIGN, SETTING, AND PARTICIPANTS: This randomized clinical trial included individuals with COPD. All individuals were enrolled in Medicare Advantage. Data were collected from January 2019 to December 2021, and data were analyzed from January 2023 to May 2024. INTERVENTION: Invitation to enroll in a program that reduced cost sharing for maintenance inhalers to $0 or $10 and provided medication management services. The random assignment of the invitation was used to estimate the effects of the invitation and program enrollment, overall and by race. MAIN OUTCOMES AND MEASURES: Inhaler adherence measured as proportion of days covered (PDC), moderate-to-severe exacerbations, short-acting inhaler fills, total spending, and as an exploratory outcome, out-of-pocket spending. RESULTS: Of 19 113 included patients, 55.2% were female; 9.5% were Black, 81.1% were White, and 9.4% were another or unknown race; and the median (IQR) age was 74 (69-80) years. Program enrollment was higher in the invited group (29.4%) than the control group (5.1%). The PDC for maintenance inhalers was higher in the invited group than the control group (32.0% vs 28.4%; adjusted invitation effect, 3.8 percentage points; 95% CI, 3.1-4.5); the adjusted effect of the program (the local average treatment effect) was 15.5 percentage points (95% CI, 12.8-18.1), a 55% relative increase in adherence. Mean (SD) out-of-pocket spending for prescriptions was lower in the invited group ($619.5 [$863.1]) than the control group ($675.0 [$887.3]; adjusted invitation effect, -$49.5; 95% CI, -68.9 to -30.0; adjusted program effect, -$203.0; 95% CI, -282.8 to -123.2), but there was no statistically significant difference in exacerbations, short-acting inhaler fills, or total spending. Among Black individuals, the adjusted invitation effect on maintenance inhaler PDC was 5.5 percentage points (95% CI, 3.3-7.7), and the adjusted program effect was 19.5 percentage points (95% CI, 12.4-26.7). Among White individuals, the adjusted invitation effect was 3.7 percentage points (95% CI, 2.9-4.4), and the adjusted program effect was 15.1 percentage points (95% CI, 12.1-18.1). The difference between the invitation effects by race was not statistically significant (1.8 percentage points; 95% CI, -0.5 to 4.1; P = .13). CONCLUSIONS AND RELEVANCE: Individuals in Medicare Advantage who received an invitation to enroll in a program that reduced cost sharing for maintenance inhalers and provided medication management services had higher inhaler adherence compared with the control group. The difference in the program's effect on inhaler adherence between Black and White individuals was substantial but not statistically significant. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT05497999.