Supplemental Oxygen for Patients with Chronic Obstructive Pulmonary Disease and Isolated Nocturnal Desaturations?

Trials in the early 1980s established the mortality benefit of nocturnal oxygen to treat patients with chronic obstructive pulmonary disease (COPD) and chronic daytime hypoxemia (i.e., oxygen saturation, ≤88%). However, treating patients with isolated nocturnal hypoxemia, not related to apnea, remains controversial. In this international trial, investigators randomized 243 patients with stable COPD and <90% oxygen saturation for >30% of home recording time in bed to receive supplemental nocturnal oxygen (titrated to oxygen saturation >90%) or ambient air through a similar concentrator for 3 to 4 years. Patients with daytime hypoxemia or obstructive sleep apnea were excluded.

At baseline, mean forced expiratory volume in 1 second (FEV₁) was 4…