PT  - JOURNAL ARTICLE
AU  - Ulrich, Silvia
AU  - Saxer, Stéphanie
AU  - Hasler, Elisabeth D.
AU  - Schwarz, Esther I.
AU  - Schneider, Simon R.
AU  - Furian, Michael
AU  - Bader, Patrick R.
AU  - Lichtblau, Mona
AU  - Bloch, Konrad E.
TI  - Effect of domiciliary oxygen therapy on exercise capacity and quality of life in patients with pulmonary arterial or chronic thromboembolic pulmonary hypertension: a randomised, placebo-controlled trial
AID  - 10.1183/13993003.002762019
DP  - 2019 Jan 01
TA  - European Respiratory Journal
PG  - 1900276
4099  - https://publications.ersnet.org//content/early/2019/05/01/13993003.002762019.short
4100  - https://publications.ersnet.org//content/early/2019/05/01/13993003.002762019.full
AB  - The question addressed by the study: We investigated whether domiciliary oxygen therapy (DOXT) increases exercise capacity and quality of life in patients with pulmonary arterial or distal chronic thromboembolic pulmonary hypertension (PAH/CTEPH) presenting with mild resting hypoxemia and exercise-induced oxygen desaturation.Materials and Methods: 30 patients with PAH/CTEPH, mean age (±sd) 60±15 y, pulmonary artery pressure 39±11 mmHg, resting pulse oximetry (SpO2) ≥90%, SpO2 drop during a 6MWD ≥4%, on PH-targeted medication, were randomised in a double-blind cross-over protocol to DOXT and placebo (ambient air) treatment, each during 5 weeks, at 3 L·min−1 via nasal cannula during nights and daytime when resting. Treatment periods were separated by 2 weeks wash-out. Co-primary outcomes were changes in 6-min walk distance (6MWD, breathing ambient air) and physical functioning scale (PF) of the short form medical outcome questionnaire (SF-36) during treatment periods.Results: DOXT increased the 6MWD from baseline 478±113 m by a mean (95%CI) of 19 m (6 to 32), and PF from 52±29 by 4 points (0 to 8). Corresponding changes with placebo were 1 m (−11 to 13) in 6MWD and −2 points (−6 to 2) in PF. Between-treatment differences in changes were 6MWD 18 m (1 to 35, p=0.042) and PF 6 points (1 to 11, p=0.029). DOXT significantly improved the NYHA functional class versus placebo.Answer to the question: This first randomised trial in PAH/CTEPH patients with exercise-induced hypoxemia demonstrates that DOXT improves exercise capacity, quality of life and functional class. The results support large long-term randomised-trial of DOXT in PAH/CTPEH.Trial registration: clinicaltrials.gov NCT01884012.FootnotesThis manuscript has recently been accepted for publication in the European Respiratory Journal. It is published here in its accepted form prior to copyediting and typesetting by our production team. After these production processes are complete and the authors have approved the resulting proofs, the article will move to the latest issue of the ERJ online. Please open or download the PDF to view this article.Conflict of interest: Prof. Dr. Ulrich reports grants from Zurich Lung League, grants from Swiss National Science Foundation, during the conduct of the study; grants and personal fees from Actelion SA, personal fees from Bayer SA, personal fees from MSD, grants and personal fees from Orpha Swiss, outside the submitted work.Conflict of interest: Ms. Saxer has nothing to disclose.Conflict of interest: Dr. Hasler has nothing to disclose.Conflict of interest: Dr. Schwarz has nothing to disclose.Conflict of interest: Mr. Schneider has nothing to disclose.Dr. Schneider has nothing to disclose.Conflict of interest: Dr. Furian has nothing to disclose.Conflict of interest: Dr. Bader has nothing to disclose.Conflict of interest: Dr. Lichtblau has nothing to disclose.Conflict of interest: Prof. Dr. Bloch reports grants from Zurich Lung League, grants from Swiss National Science Foundation, during the conduct of the study.