24-Hour Oxygen Therapy fails to Add Survival Benefit Over 15-Hour oxygen Therapy for Severe Hypoxemia: NEJM

A recent study published in the New England Journal of Medicine journal found that extending long-term oxygen therapy (LTOT) to 24 hours a day provides no added survival benefit when compared to 15 hours of oxygen therapy per day for patients with severe hypoxemia. After 4 years of data collection, this study challenged the long-held assumption that continuous oxygen supplementation is more effective in reducing hospitalizations and deaths.

Long-term oxygen therapy has been a recommended treatment for patients with chronic, severe hypoxemia, where the oxygen supplementation is recommended for at least 15 hours daily to improve survival rates. However, previous nonrandomized comparisons suggested that using oxygen for 24 hours might provide additional benefits which could lead to a more burdensome regimen for patients. Thereby, Magnus Ekström and team initiated a trial to determine whether patients receiving oxygen therapy for 24 hours a day had a lower risk of hospitalization or death when compared to the individuals who were treated for 15 hours a day.

The trial was conducted between May 2018 and April 2022 and involved a total of 241 patients diagnosed with chronic, severe hypoxemia. These participants were randomly assigned to receive either 24 hours or 15 hours of oxygen therapy per day. The primary measure of the study used a time-to-event analysis to assess the differences in risk between the two treatment groups, over a 12-month period. Secondary outcomes included the rates of individual hospitalizations and deaths at 3 and 12 months.

The study revealed no significant difference between the two groups in terms of hospitalization or death after one year of follow-up. Also, the patients in the 24-hour group reported a median daily oxygen usage of 24 hours, while the ones in the 15-hour group reported a median of 15 hours. Despite the extended oxygen usage, the rate of hospitalization or death in the 24-hour group (124.7 events per 100 person-years) was nearly identical to that of the 15-hour group (124.5 events per 100 person-years). The hazard ratio was 0.99 which indicated no statistically significant reduction in risk for the 24-hour regimen.

Further analysis showed no substantial differences in hospitalization rates, mortality, or adverse events between the two groups. Overall, the findings suggest that long-term oxygen therapy for 24 hours per day does not confer additional benefits over a 15-hour regimen in reducing hospitalizations or death within a year.

Source:

Ekström, M., Andersson, A., Papadopoulos, S., Kipper, T., Pedersen, B., Kricka, O., Sobrino, P., Runold, M., Palm, A., Blomberg, A., Hamed, R., Lindberg, E., Sundberg, B., Hadziosmanovic, N., Björklund, F., Janson, C., McDonald, C. F., Currow, D. C., & Sundh, J. (2024). Long-Term Oxygen Therapy for 24 or 15 Hours per Day in Severe Hypoxemia. In New England Journal of Medicine. Massachusetts Medical Society. https://doi.org/10.1056/nejmoa2402638