Home oxygen has no benefit in patients with COPD and moderate hypoxemia: Lancet

USA: A new study published in The Lancet Respiratory Medicine suggests that patients with chronic obstructive pulmonary disease (COPD) and mild hypoxemia are likely to have little to no difference in 3-year mortality while using home oxygen. The findings do not support the widespread use of home oxygen in this patient population.

In patients with severe hypoxemia and COPD, long-term oxygen treatment (LTOT) increases survival. Uncertainty exists over the optimal way to handle mild hypoxemia (including isolated nocturnal desaturation) that does not meet the criteria for LTOT. In order to determine the impact of home oxygen therapy (LTOT or nighttime oxygen therapy) on overall survival in patients with COPD and mild hypoxemia, Yves Lacasse and colleagues undertook this study.

Embase, MEDLINE, the Cochrane Central Register of Controlled Trials, CINHAL, and the Web of Science were searched for parallel-group randomized trials of long-term or nocturnal oxygen in patients with COPD and mild daytime hypoxemia or isolated nocturnal desaturation, or both, between the creation of the database and January 13, 2022. Throughout the course of the trial, control groups got standard treatment or ambient air via concentrators (placebo). The 3-year mortality rate was the main outcome of interest. Excluded were trials involving oxygen in cases of severe hypoxemia and crossover studies.

Two reviewers reviewed the full-text articles, reference lists, and titles of pertinent research using inclusion and exclusion criteria. A standardized data collection form was used to manually extract aggregate data twice. The Cochrane Risk of Bias Tool was used to evaluate the methodological quality. Individual papers were combined using a random-effects meta-analysis. The relative risk decrease in death at three years of follow-up was thought to be the least clinically significant difference for home oxygen of 30–40%.

The key findings of this study were as follows:

1. After eliminating duplicates, 2192 studies were found, of which 1447 were reviewed, 161 underwent full-text screening, and six were determined to be appropriate for inclusion.

2. The excellent quality of the evidence was presented in these six randomized studies, which were published between 1992 and 2020.

3. The impact of home oxygen in lowering 3-year mortality was found to be modest or missing in the primary meta-analysis (five trials; 1002 patients).

4. Hence, the lower limit of the 95% confidence interval did not satisfy the prespecified minimal clinically relevant difference.

In conclusion, from the findings of this study, it is clear that in this patient population, the statistics do not support the widespread use of home oxygen.

Reference:

Lacasse, Y., Casaburi, R., Sliwinski, P., Chaouat, A., Fletcher, E., Haidl, P., & Maltais, F. (2022). Home oxygen for moderate hypoxaemia in chronic obstructive pulmonary disease: a systematic review and meta-analysis. In The Lancet Respiratory Medicine. Elsevier BV. https://doi.org/10.1016/s2213-2600(22)00179-5