Feasibility, quality and added value of unsupervised at-home spirometry in primary care.

Introduction: Home-based portable spirometry could be a flexible alternative to standard spirometry for the diagnosis and monitoring of obstructive pulmonary disease. However, it is unknown whether implementation in a real-world primary care setting is practicable and produces good quality spirometry. Method: We studied feasibility, quality and added value of at-home spirometry, using the NuvoAir Air Next Spirometer in primary care practice in the Netherlands and Sweden. Adults with an asthma- or COPD-related spirometry indication were provided with equipment to perform spirometry at-home, including explanations from their healthcare provider (HCP). Spirometry was performed unsupervised at home (only written/video instructions available), followed by an HCP-office standard-of-care spirometry assessment. Differences in FEV1 and FVC-values from home and office were compared. Home spirometry was assessed by the NuvoAir-software according to ATS/ERS guidelines. Quality grades A and B were considered acceptable, A-C considered clinically useful. Questionnaires on lung disease status were completed by participants. Questionnaires on experience with spirometry at-home were completed by participants and their HCPs. Results: Of 144 enrolled participants, 125 patients (86.7%) could complete a spirometry session using the app. Of those able to produce spirometry, 65% considered it beneficial for their disease monitoring, 59.2% produced acceptable spirometry, and 66.4% provided clinically useful results. Few HCPs saw added value for improving diagnoses (12%), however, 70% saw added value for disease monitoring, and 47% indicated they would like to implement it. Spirometry parameter values were marginally higher at-home than in the HCP-office (Figure 1). Discussion: Some patients will not be able to perform spirometry at home after technical difficulties with the app. However, HCPs and most participants rated it as feasible and of added value for asthma and COPD monitoring in primary care, though less helpful for diagnostic purposes. No substantial systematic bias in spirometry results was observed in unsupervised measurements.