REDOX Trial: Long-Term Oxygen Therapy for 24 or 15 Hours per Day in Severe Hypoxemia
The REDOX trial is a phase IV, registry-based, randomized controlled study that examines whether long-term oxygen therapy (LTOT) for 24 hours per day provides better outcomes compared to LTOT for 15 hours per day in patients with severe hypoxemia.
Objective:
The primary goal of the trial is to determine whether LTOT prescribed continuously for 24 hours/day reduces the rate of all-cause hospitalization or death at one year compared to LTOT for 15 hours/day in patients with severe hypoxemia.
Study Population:
- Total Patients: 241
- Inclusion Criteria:
- Patients aged 18 years or older with severe resting hypoxemia (PaO₂ < 8.0 kPa on air).
- Patients with signs of heart failure or polycythemia (EVF > 0.54).
- Exclusion Criteria:
- Smoking or contact with open fire.
- Unsafe compliance with LTOT.
- Already on LTOT for more than 28 days.
Study Groups:
- LTOT 24 Hr/Day Group: 117 patients received oxygen therapy for 24 hours a day.
- LTOT 15 Hr/Day Group: 124 patients received oxygen therapy for 15 hours a day.
Primary Outcome:
The primary outcome was a composite of hospitalization or death from any cause within one year, measured in events per 100 person-years.
Outcome Rates:
- LTOT 24 Hr/Day Group: 124.7 events per 100 person-years.
- LTOT 15 Hr/Day Group: 124.5 events per 100 person-years.
- Hazard Ratio (HR): 0.99, 95% CI: 0.72–1.36, P-value: 0.007.
Secondary Outcome:
The secondary outcome was the occurrence of any adverse event:
- LTOT 24 Hr/Day Group: 8 adverse events.
- LTOT 15 Hr/Day Group: 9 adverse events.
Conclusion:
Among patients with severe hypoxemia, long-term oxygen therapy for 24 hours per day did not result in a lower risk of hospitalization or death within one year compared to therapy for 15 hours per day. Both regimens showed similar outcomes in terms of primary and secondary endpoints.
Reference: Ekström M et al. N Engl J Med. 2024;391:977-988.