Ambulatory oxygen for treatment of exertional hypoxaemia in pulmonary fibrosis (PFOX): a multicentre, randomised, sham-controlled trial
Anne E Holland, Mariana Hoffman, Tamera J Corte, Daniel C Chambers, Graham Hepworth, Magnus P Ekström, Ian Glaspole, Nicole S.L. Goh, Yet H Khor, Andrew Palmer, Carly Barton, Ingrid A. Cox, Leona Dowman, Jonas Einarsson, Lisa Fuhrmeister, John A. Mackintosh, Pernilla Neglén, Jyotika D Prasad, Jessica Bucciarelli, Simon Scherp, Magnus Sköld, Natasha Smallwood, Karen Symons, Michelle Thompson, Christine F McDonald
Abstract
BACKGROUND: Ambulatory oxygen therapy can be used to treat exertional hypoxaemia during daily life activities in people with fibrotic interstitial lung disease (ILD). However, evidence for its efficacy is scarce. This trial aimed to compare the effects of ambulatory oxygen with ambulatory air on physical activity in daily life over 6 months in people with fibrotic ILD and isolated exertional hypoxaemia. METHODS: ] ≤88% on 6-min walk test). Participants were randomly assigned (1:1) to receive ambulatory oxygen during daily activities delivered using a portable oxygen concentrator (Inogen One G3HF), or air delivered using a device identical in appearance, display, weight, and operation (sham). The primary outcome was change in physical activity (mean steps per day) at 3 months, measured using the StepWatch activity monitor in the intention-to-treat population. The trial is registered with ClinicalTrials.gov (NCT03737409) and is completed. FINDINGS: Between Aug 6, 2019, and Jan 10, 2024, 614 individuals were assessed for eligibility. 116 were randomly assigned to ambulatory oxygen (n=59) or ambulatory air (n=57). 79 (68%) of 116 participants were male and 37 (32%) were female. Mean age was 71 years (SD 10). There was no significant difference between ambulatory oxygen (-271 steps per day, 95% CI -702 to 161) and ambulatory air (64, -377 to 505) for change in mean steps per day at 3 months (-334, -803 to 134). There were no serious adverse events related to study treatments, and no difference between groups for the number or type of adverse events. INTERPRETATION: In people with fibrotic ILD and exertional hypoxaemia, ambulatory oxygen delivered using a portable concentrator did not provide benefits over ambulatory air for physical activity in daily life. Routine prescription of ambulatory oxygen using a portable oxygen concentrator for people with fibrotic ILD with isolated exertional hypoxaemia might not be indicated. These results reinforce the pressing need for innovation in portable oxygen devices to ensure effective oxygen delivery and acceptability to patients. FUNDING: National Health and Medical Research Council (Australia) and Swedish Society of Medicine.