LAUSR

Long-term oxygen therapy (LTOT) is universally accepted as standard care for patients with severe resting hypoxaemia, irrespective of underlying diagnosis, with the aim being to improve patient survival. COPD and fibrotic interstitial lung disease (ILD) are the two most common indications for LTOT globally [1–4]. As therapeutic benefits of LTOT have only been established in patients with COPD [5, 6], current prescribing recommendations are based on the study entry criteria used in the pivotal clinical trials of LTOT in COPD [5, 6]. Patients with ILD have significantly worse survival after commencing LTOT than patients with COPD [7, 8]. Despite fibrotic ILD and COPD sharing similar clinical presentations, there are marked differences in their pathophysiology. The significance of differing severities of resting hypoxaemia and therapeutic effects of LTOT have not been explored in the ILD population [9]. It is unknown whether the current oxygen prescribing threshold for LTOT established in patients with COPD is appropriate for patients with fibrotic ILD. This study aimed to evaluate the significance of moderate resting hypoxaemia in fibrotic ILD. We hypothesised that moderate resting hypoxaemia would be an independent prognostic factor for survival in ILD and there would be a difference in survival between fibrotic ILD and COPD patients with moderate resting hypoxaemia. Moderate resting hypoxaemia is an independent prognostic factor in fibrotic ILD. Potential therapeutic effects of reversing moderate resting hypoxaemia need to be evaluated in this population. https://bit.ly/30PFtoC