The observational study consists in collecting physiological data (cardiorespiratory and physical activity) and use of the oxygen therapy device in real life during the first months after the initiation of treatment.~For this purpose, two connected medical devices will be provided to each patient during 2 periods of 2 weeks (weeks 6 to 8 then weeks 12 to 14 after the initiation of oxygen therapy). The devices are: 1/ a connected watch that continuously measures vital parameters (heart rate and blood oxygen saturation), and physical activity parameters (no. of steps, distance, duration of effort), and 2/ a Teleox device that remotely monitors patients equipped with an oxygen source (it measures the oxygen flow rate requested by the patient, the duration of use of the oxygen source, and the breathing rate).~Study design: a cohort of 250 patients with COPD newly initiated a long term oxygen therapy will be enrolled in the study and follow-up over 6 months. Data will be collected by lung specialists and home health care provider teams at 2 months, 3.5 months and 6 months post-initiation of oxygen therapy.
Background : Long-term oxygen therapy is prescribed for patients with severe COPD. The aim of oxygen therapy is to administer oxygen at a concentration level higher than that of ambient air, in order to treat or prevent the symptoms and manifestations of arterial hypoxemia; this therapy can be applied either in an acute situation or as a long-term treatment, in cases of stabilized severe chronic hypoxemia.~Currently, pneumologists do not have the possibility, between 2 consultations spaced several months apart, to measure the patient's compliance with the treatment (adherence to oxygen therapy) nor the respect of the prescribed dosage (O2 flow and duration). In addition to the patient's adherence to the treatment, the specialist does not have the possibility to assess the patient's physical activity (walking ...).~This observational study is a e-health, prospective, multicenter study conducted in France under the control of pneumologists.~The main objective of this study is to evaluate the adherence to oxygen therapy in real life, and its evolution, in COPD patients justifying a long term oxygen therapy in stable state.