Higher short-acting beta-agonist use is associated with greater COPD burden.

INTRODUCTION: The COPD Assessment Test (CAT) is a self-administered questionnaire that measures symptomatic burden. CAT is used as part of the Global Initiative for Chronic Obstructive Lung Disease (GOLD) guidelines refined ABCD tool and is usually performed during office visit assessment. Electronic medication monitors (EMMs) capture utilization of short-acting beta-agonists (SABA) that may indicate disease worsening in real-time. The primary objective was to assess the relationship of CAT with SABA utilization. METHODS: From 8/2017-1/2019, COPD patients ≥40 years of age were enrolled in a digital health platform consisting of EMMs and a mobile application to track time and date of SABA use. Patients with a completed CAT and ≥81 days of continuous EMM data were included in analyses. Using one-way ANOVA, SABA use and maintenance medication adherence were compared by CAT score categories: <10 (low burden), 10-20 (medium), 21-30 (high), and 31-40 (very high). Associations were additionally estimated in patients who used ≥1 puff/week of their rescue and maintenance medication. RESULTS: The population included 2196 COPD patients (mean age: 60 years). CAT scores from low to high burden were associated with greater SABA use, from 0.8 to 1.9 puffs/day (+1.1 [95% CI: 0.6, 1.6 puffs/day], P < 0.001), and lower adherence, from 69% to 59%, (-10% [95% CI: -1, -19%], P = 0.04). Sensitivity analyses yielded similar results. CONCLUSIONS: This study found a significant association between greater SABA use and lower adherence with higher burden CAT scores. This finding may suggest that passive collection of inhaled medications could serve as a surrogate for CAT.