Multicentre randomised placebo-controlled trial of nocturnal oxygen therapy in chronic obstructive pulmonary disease

INTERVENTION: 1. Nocturnal oxygen therapy group: N‐O2 will be delivered overnight to allow the oxygen saturation to be greater than 90% 2. Placebo: the patients allocated in the control group will receive room air delivered by sham concentrator CONDITION: Chronic obstructive pulmonary disease (COPD) ; Respiratory ; Chronic obstructive pulmonary disease (COPD) PRIMARY OUTCOME: The primary outcomes of this trial are mortality from all cause or requirement for LTOT (composite outcome). SECONDARY OUTCOME: 1. Quality of life and utility measures; 2. Costs from a societal perspective ; 3. Compliance with oxygen therapy INCLUSION CRITERIA: 1. Patients with a diagnosis of COPD supported by an history of past or current smoking and obstructive disease with forced expiratory volume in one second (FEV1)/forced vital capacity (FVC) less than 60% 2. Presence of mild‐to‐moderate daytime hypoxemia with a daytime partial pressure of oxygen in arterial blood (paO2) in the range of 56 ‐ 69 mmHg 3. Patients fulfilling our definition of nocturnal oxygen desaturation: greater than or equal to 30% of the recording time with transcutaneous arterial oxygen saturation less than 90% on two consecutive recordings