Ambulatory Oxygen Improves Health Status in ILD Patients

Data show that ambulatory oxygen improves the status of health in patients with fibrotic interstitial lung diseases (ILDs), according to Dina Visca, MD, at 2017 American Thoracic Society (ATS) Conference.

By the study’s end, the data showed that ambulatory oxygen improved symptoms, performance, and recovery time compared with placebo. The novel findings of this study are expected to influence future ILD-specific guidelines for ambulatory use, the researchers noted.

“At the end of each treatment period, we asked an easy question to the patient,” said Visca, University of Parma, Italy. “Is breathlessness worse, the same, or better. We saw that all patients, except one, on oxygen felt better or the same, and all patients, except one, on air, felt the same or worse.”

Fibrotic ILDs are often progressive, chronic conditions, resulting in considerable morbidity and mortality. Closely associated with that worsening quality of life in patients with this disorder is shortness of breath, or breathlessness, a symptom often linked to oxygen desaturation on exertion. This symptom increasingly limits the capability of patients to participate in everyday activities, and it can eventually affect their overall independence.

Ambulatory oxygen has long been assumed to improve the 6-minute walk test (6MWT) performance in ILD patients, but no real-life studies had ever been conducted to this point. It is also commonly prescribed in clinical practice, but, despite this, there are still no guidelines on ambulatory oxygen.

The study, presented by Visca, assessed whether individuals with fibrotic ILD whose SaO2 falls to ≤88% on a 6MWT, but are not hypoxic at rest, find the use of ambulatory oxygen in their daily lives beneficial, by assessing shifts in the status of their health.

Two hundred sixty-nine patients were tested, and 76 completed the study.

Inclusion criteria for patients participating in the study included: patients with fibrotic ILD, oxygen desaturation less than or equal to 88% on a 6-minute walk test (6MWT) on room air, but normal Sa02 at rest (greater than or equal to 94%), and stable respiratory symptoms and no changes in mediation over 4-week period preceding the active part of the study.

There was a 3.7% improvement in King's brief interstitial lung disease with the use of ambulatory oxygen versus no oxygen use (95% CI, 1.8-5.7; P <.0001). Breathlessness and activity were also improved with oxygen versus without, with a difference of 8.7% (95% CI, 4.8-12.6; P <.0001). There was also a 7.6% difference in chest symptoms between the groups (95% CI, 1.9-13.2; P = .009).

Sensitivity analyses included adjustment for any covariates associated with the primary outcome. These may have included baseline age, gender, smoking history, Body Mass Index (BMI), ILD severity, and other factors. Additionally, patient-reported consumption of oxygen cylinders was factored in as a covariate. In these analyses, oxygen use remained superior.

Visca D, Mori L, Tsipouri V, et al. AmbOx: A Randomised Controlled, Crossover Trial Evaluating the Effects of Ambulatory Oxygen on Health Status in Patients with Fibrotic Interstitial Lung Disease. Presented at: 113th ATS Annual Meeting; Washington, DC, May 19-24.