Feasibility of Home-Based Spirometry Monitoring as a Decentralized Clinical Trial Component in Patients with Chronic Obstructive Pulmonary Disease and Other Respiratory Diseases.

INTRODUCTION: Home-based spirometry has emerged as a potential component of decentralized clinical trials (DCTs) in respiratory medicine, but its real-world feasibility in patients with chronic obstructive pulmonary disease (COPD) and other respiratory diseases remains insufficiently characterized. This study evaluated the feasibility of remote pulmonary function monitoring using a portable spirometer and mobile application in adults with COPD or other respiratory diseases. METHODS: This exploratory single-arm study enrolled adults aged 19 years or older with COPD or other respiratory diseases. Participants were asked to perform home-based spirometry at six prespecified time points (Days 15, 29, 43, 57, 71, and 85). Feasibility was assessed using visit-level and participant-level adherence, spirometry quality grades, and patient-reported usability and satisfaction. Participants completing at least 5 of 6 scheduled measurements were classified as the high-adherence group; this cut-off was an operational, study-specific definition. RESULTS: A total of 30 participants were enrolled (19 with chronic obstructive pulmonary disease, 5 with asthma, 2 with asthma-COPD overlap, and 4 with other respiratory conditions), and 23 completed the study. Visit-level completion rates declined over time, from 88.5% on Day 15 to 47.8% on Day 71 and 56.5% on Day 85. Nine participants completed all six measurements, while 13 completed at least five. Portable spirometry quality showed variability across visits, with both high-quality and low-quality measurements observed. Compared with the low-adherence group, the high-adherence group reported significantly higher scores for convenience, communication with the research team, overall satisfaction, willingness to participate in future telemedicine-based trials, device training adequacy, ease of device use, and application usability. CONCLUSIONS: Home-based spirometry may be a useful decentralized trial component in patients with COPD and other respiratory diseases; however, the decline in adherence over time and the variability in measurement quality indicate that substantial operational refinement is needed before broader implementation. Because no feasibility threshold was prespecified, no concurrent laboratory spirometry comparison was performed, and the study population was diagnostically heterogeneous, these findings are exploratory and address operational feasibility rather than measurement validity.