Background:
Pulmonary function testing is one of the key investigations for monitoring disease progression in patients with interstitial lung disease (ILD). Home monitoring has shown to be beneficial and highly informative in monitoring patients with idiopathic pulmonary fibrosis (IPF) but little data supports its use in other ILDs. We aim to determine if home spirometry and oximetry monitoring is feasible in patients with a broad selection of patients with ILD.
Methods:
Patients with connective tissue disease related ILD (CTD-ILD), IPF and familial pulmonary fibrosis (FPF) were recruited in this observational cohort study. They were provided with a handheld spirometer and finger oximeter which pairs with a smartphone app (patientMpower) generating a real-time electronic health journal. Patients were asked to perform daily FVCs for one year.
Results:
We recruited 62 patients with CTD-ILD, 31 IPF and 21 FPF. 47.8% were male. The median ages were 66, 71 and 69 years respectively. Preliminary data at 6 months for 99 patients demonstrated a median FVC predicted of 83.0% in the CTD-ILD, 85.3% in IPF and 83.1% in FPF cohorts. The median follow-up was 239 days. The median oxygen saturation (SpO2) for 10558 readings was 96% in all three cohorts.
| CTD-ILD | IPF | FPF | |
| No. of Patients | 54 | 28 | 17 |
| No. of FVC Readings | 5624 | 3789 | 1808 |
| Median Days | 252 | 268 | 250 |
| Median FVC (L) | 2.35 | 2.66 | 2.05 |
| Median FVC Predicted (%) | 83.0 | 85.3 | 83.1 |
| No. of SpO2 Readings | 4991 | 3745 | 1852 |
| Median SpO2 (%) | 96 | 96 | 96 |
Conclusion:
Performing FVC remotely is feasible in patients with ILD and generates clinically meaningful data to monitor disease progression, allowing timely intervention.