Health-related quality of life in patients with interstitial lung disease (ILD) and isolated exertional hypoxia may be improved by the use of ambulatory oxygen, especially in those who have fewer therapeutic options, according to a study published in The Lancet Respiratory Medicine.
To assess the effect of using ambulatory oxygen on health-related quality of life in patients with isolated exertional hypoxia from ILD, investigators conducted an open-label, prospective, mixed-method, randomized, crossover, controlled, multicenter clinical trial (ClinicalTrials.gov Identifier: NCT02286063) from September 10, 2014 to October 5, 2016. Eligible participants (N=84) were 18 or older, had fibrotic ILD, reported stable respiratory symptoms during the 2 weeks prior, and fell from nonhypoxic at rest to a transcutaneous arterial oxygen saturation of ≤88% during a 6-minute walk test.
Participants were randomly assigned 1:1 into an oxygen or no oxygen treatment group for 2 weeks, followed by 2 additional crossover weeks (41 began with ambulatory oxygen, and 43 began with no oxygen). The researchers measured primary outcomes through change in the King’s Brief ILD questionnaire (K-BILD) score after 2 weeks of oxygen treatment compared with no treatment for 2 weeks.
Of the 84 participants, 76 completed the trial. Ambulatory oxygen was associated with significantly improved total K-BILD scores (oxygen: mean 55.5 [SD 13.8] vs no oxygen: 51.8 [13.6]; mean difference adjusted for treatment order 3.7 [95% CI, 1.8-5.6]; P <.0001) as well as the subdomains of breathlessness and activity (mean difference 8.6 [95% CI, 4.7-12.5]; P <.0001) and chest symptoms (7.6 [95% CI, 1.9-13.2]; P =.009). The effect on the test’s psychological subdomain, however, was not significant (2.4 [95% CI, –0.6 to 5.5]; P =.12).
A total of 5 serious adverse events occurred (including 1 death in each group), but none of these were treatment related. Upper respiratory tract infections were the most common adverse events, with 1 occurring in the no treatment group and 3 occurring in the oxygen treatment group.
The investigators concluded that “[a]mbulatory oxygen use was associated with reduced exertional hypoxia and dyspnoea on 6 [minute walk tests] and seemed to improve [health-related quality of life] in patients with fibrotic[ILD].” They also stated that additional studies will be needed to better assess these effects and to develop specific guidelines for the use of ambulatory oxygen in patients with ILD.
Disclosures: The study was funded by the UK National Institute for Health Research. See article for full list of authors’ disclosures.
Visca D, Mori L, Tsipouri V, et al. Effect of ambulatory oxygen on quality of life for patients with fibrotic lung disease (AmbOx): a prospective, open-label, mixed-method, crossover randomised controlled trial [published online August 28, 2018]. Lancet Respir Med. doi:10.1016/S2213-2600(18)30289-3