Late Breaking Abstract - Effect of oxygen supplementation on sleep and nocturnal breathing in patients with chronic obstructive pulmonary disease travelling to high altitude: randomized trial

Objectives: We evaluated whether nocturnal oxygen administration improves sleep and breathing disturbances in lowlanders with chronic obstructive pulmonary disease (COPD) staying for 2 nights at 2048m. Methods: 21 lowlanders with COPD, median age 68y, FEV1 55%predicted, travelled to a mountain village at 2048m (St. Moritz) twice for 2 days, separated by a 2 week washout period at <800m. During nights at 2048m, oxygen or ambient air (sham) was administered by nasal cannula at 3l/min according to a randomized, blinded, cross-over design. Co-primary outcomes were mean nocturnal oxygen saturation (SpO2) and apnea/hypopnea index (AHI) measured during polysomnography. Results: Oxygen supplementation decreased AHI and increased SpO2 compared to sham at 2048m (table). Conclusion: Lowlanders with COPD experience pronounced hypoxemia and restriction of sleep in the first night at 2048m that prevents by nocturnal oxygen supplementation. Our study provides novel data to counsel COPD patients travel to altitude