# Real-world clinical and economic outcomes associated with supplemental oxygen therapy use among patients with fibrosing interstitial lung disease in the United States

## TL;DR

This study finds that using supplemental oxygen therapy in patients with fibrosing interstitial lung disease is linked to higher mortality and healthcare costs, likely due to more advanced disease.

## Contribution

The study provides real-world evidence on the clinical and economic outcomes of oxygen therapy in fibrosing ILD patients in the U.S.

## Key findings

- Patients using oxygen therapy had significantly higher mortality compared to those who did not.
- Oxygen therapy was associated with increased hospitalizations and healthcare resource utilization.
- Higher healthcare costs were observed in the oxygen therapy group for both all-cause and fibrosing ILD-related care.

## Abstract

Patients with fibrosing interstitial lung disease (ILD) experience a decline in lung function with progressive symptoms, poor response to treatment, and reduced quality of life. While supplemental oxygen therapy is commonly prescribed in clinical practice for patients with fibrosing ILD, the long-term outcomes associated with oxygen therapy remain unclear. This study aimed to address this knowledge gap.

This non-interventional study used the Optum® Market Clarity database from 01 October 2015 to 30 June 2022. Patients aged ≥ 18 years with newly diagnosed fibrosing ILD (≥ 2 fibrosing ILD diagnoses on different service dates within 365 days) were included. Patients meeting initial selection criteria were assigned to cohorts based on oxygen therapy initiation. Patients who initiated oxygen therapy following the ILD diagnosis (oxygen therapy cohort) were propensity scores matched 1:1 to those who did not yet initiate oxygen therapy (no oxygen therapy cohort). The oxygen cohort’s index date was the first oxygen therapy date. For the no oxygen therapy cohort, it was assigned using the time between the fibrosing ILD diagnosis date and the index date of a matched oxygen therapy patient. Follow-up continued until health plan disenrollment, death, or end of study period (follow-up period).

A total of 24,680 patients who initiated oxygen therapy were successfully matched to those who did not. The mean age of the study cohort was 68.9 years and 50.9% were male. Mortality was significantly higher in the oxygen cohort vs. the no oxygen cohort (54.0% vs. 26.3%, p < 0.001). Similar trends were observed for hospitalizations and probable acute exacerbations. The oxygen cohort had significantly higher all-cause healthcare resource utilization (HCRU) across all categories and incurred greater total all-cause healthcare costs. Similar patterns were seen in fibrosing ILD-related HCRU and costs.

Initiation of oxygen therapy in patients with fibrosing ILD is associated with significantly higher mortality, increased hospitalizations, and greater healthcare utilization and costs. However, these findings do not imply that oxygen therapy causes harm; rather, oxygen use likely reflects more advanced or rapidly progressing ILD. These results highlight the need for earlier and more effective interventions to delay disease progression and reduce the burden of care.

The online version contains supplementary material available at 10.1186/s12890-025-03909-1.