Similar risk of hospitalization and mortality for patients continuing and discontinuing LTOT

While the characteristics and medical management of patients treated with long-term oxygen therapy (LTOT) have transformed during the last decades, the evidence base for LTOT itself remains largely unchanged. This study aimed to compare the risk of hospitalization and death among hypoxemic patients discontinuing LTOT, with that of controls continuing therapy.

This was a retrospective observational study of patients with LTOT included in the DISCOVERY cohort, using elements of target trial emulation. Patients who fulfilled LTOT criteria but discontinued treatment with LTOT within 90 days of initiation, not due to improving oxygenation or change of treatment modality, were identified. The risk of hospitalization and death as a composite outcome, and the risks of individual outcomes of hospitalization and death, were compared with age-, sex- and disease type-matched controls who continued LTOT, using Cox regression adjusted for confounders.

In total, 79 patients discontinuing LTOT and 395 controls were analyzed, both groups with a mean age of 73 (SD ± 11) years, 72% females, 65% underlying COPD. In adjusted Cox regression models, discontinuing LTOT was not associated with an increased risk of hospitalization or death (hazard ratio (HR) 1.0 95% Confidence interval (CI) 0.78-1.3), hospitalization (HR 0.99 95% CI 0.75-1.3), or death (HR 0.79 95% CI 0.61-1.0).

In this study, patients fulfilling LTOT initiation criteria who discontinued therapy were not found to be at an increased risk of hospitalization or death, suggesting equipoise for a randomized trial of LTOT discontinuation or non-initiation in selected patient groups.