Feasibility of online home spirometry in systemic sclerosis–associated interstitial lung disease: a pilot study

OBJECTIVES: Frequent monitoring of forced vital capacity at home may be of added value in patients with SSc-associated interstitial lung disease (SSc-ILD) to monitor disease progression and guide treatment decisions. The aim of this study was to evaluate the feasibility and optimal frequency of online home spirometry using a home monitoring application in patients with SSc-ILD. METHODS: This was a prospective, observational study in patients with SSc-ILD. Patients evaluated for 3 months the online home monitoring application ILD-online integrated with a Bluetooth-connected spirometer. Patients performed daily home spirometry for 6 weeks and weekly home spirometry for 6 weeks. In addition, patients completed an evaluation questionnaire after 3 months and online patient-reported outcomes at baseline and 3 months. RESULTS: Ten consecutive patients participated. Mean adherence to home spirometry was 98.8% (s.d. 1.5). Home and hospital spirometry were highly correlated. The mean coefficient of variation was lower for weekly [2.45% (s.d. 1.19)] than daily [3.86% (s.d. 1.45)] forced vital capacity measurements (P = 0.005). All patients considered the home monitoring application and spirometer easy to use and no patients considered home spirometry burdensome. All patients would recommend home monitoring to other patients with SSc. CONCLUSIONS: Home spirometry using an online home monitoring application is feasible in patients with SSc-ILD, with high adherence and patient satisfaction. Larger long-term studies are needed to assess whether home spirometry can detect the progression of ILD in patients with SSc.