RESUMEN
Introduction/Aim: Home spirometry may improve respiratory disease monitoring and management and mitigate the decline in testing exacerbated by COVID-19. Smartphone-connected spirometers could allow patients to conduct spirometry independently without the need to travel to lung function clinics. This study assessed the accuracy of a personal spirometer and the feasibility of unsupervised home spirometry. Method(s): Subjects (19-88 years) with (n = 44) and without (n = 20) respiratory disease, were recruited and supervised to perform spirometry on a standard desktop spirometer (MGC Diagnostics) and a personal ultrasonic spirometer (SpiroHome) in the clinical laboratory. Unsupervised testing was subsequently conducted using the SpiroHome at the subjects' home (2 tests/week for 3 weeks). Subjects returned to the clinic to conduct an exit survey which assessed their willingness to adopt a personal spirometer into their long-term care plan. Comparisons between desktop and personal spirometry, as well as supervised and unsupervised spirometry, were compared by Bland-Altman analysis (%Bias +/- CI) and Pearson's correlation. Result(s): The proportion of tests meeting American Thoracic Society/European Respiratory Society criteria (80%) remained constant across clinic and home spirometry sessions for subjects who completed 3 weeks of home testing (p = 0.73, Fisher's exact test, n = 61). Supervised spirometry on the SpiroHome (n = 56) reliably measured FEV 1 (-3.12+/-27.01%;r=0.98, p < 0.0001) and FVC (-0.38+/-22.91%;r=0.99, p < 0.0001) producing a small underestimation compared to desktop spirometry. Unsupervised home spirometry (when performed <24 hrs from the clinic appointment) on the SpiroHome (n = 51) produced a small underestimation of FEV 1 (-2.41+/-35.57%;r=0.96, p < 0.0001) and a slight overestimation of FVC (0.08+/-24.70%;r=0.98, p < 0.0001) compared with supervised manoeuvres in the clinical laboratory. Conclusion(s): Findings indicate that lung function assessed by SpiroHome compares well with in-clinic standard desktop spirometry across a range of diseases and severities in both the clinic and home settings. A larger cohort of subjects are being recruited to confirm the accuracy and the overall utility of personal spirometry.