Clinical question: Does using supplemental oxygen in patients with stable chronic obstructive pulmonary disease (COPD) result in a longer time to death or first hospitalization?
Background: Previous trials have shown that use of long-term, supplemental oxygen in COPD and severe resting hypoxia reduced mortality, however, data is inconclusive if its use in mild-moderate COPD has the same effect.
Study design: Parallel-group, randomized, unblinded clinical trial.
Dr. Claire Ciarkowski
Setting: Outpatient clinical centers.
Synopsis: Researchers randomized 738 patients from 42 outpatient centers with stable COPD and moderate resting desaturation (SpO2, 89%-93%) or moderate exercise induced desaturation (6-minute walk test, SpO2 greater than 80% for five minutes, and greater than 90% for 10 seconds) to long-term supplemental oxygen or no supplemental oxygen. Time-to-event analysis found no differences in the composite primary outcome of death or first hospitalization (HR, 0.94; 95% confidence interval, 0.79-1.12), or in any other secondary outcomes of COPD exacerbations, or COPD-related or all-cause hospitalizations.
Limitations included lack of blinding, possible exclusion of patients with higher COPD severity, and lack of assessment of immediate effects of oxygen on symptoms or exercise performance.
Bottom line: Long-term, supplemental oxygen provided no benefit in mortality or time to first hospitalization among other outcomes in patients with stable COPD and resting or exercise-induced moderate desaturations.
Citation: The Long-Term Oxygen Treatment Trial Research Group. A randomized trial of long-term oxygen for COPD with moderate desaturation. N Engl J Med. 2016;375:1617-27.
Dr. Ciarkowski is a clinical instructor at the University of Utah School of Medicine and an academic hospitalist at the University of Utah Hospital.