The purpose of this prospective cohort study is to determine factors involved in survival in new COPD patients treated by long-term oxygen therapy.

Background: long-term oxygen therapy is indicated in patients with severe COPD. No studies have been performed in the past 20-25 years to examine the results of early clinical trials. Further studies are necessary to understand the utility of oxygen therapy in severe COPD.

long-term oxygen therapy prolongs life in patients with severe COPD and severe resting hypoxemia. The objective of this study is to measure the survival in relation to the level of initial resting hypoxemia, serious co-morbidities, and nutritional status in COPD patients treated by long-term oxygen therapy. After enrollment at the beginning of oxygen therapy, following data will be collected during 3 years. Lung function, blood gas analysis, exercise capacity measured by the 6-Min Walk Distance test (6-MWD), dyspnea scale, BODE index, quality of life, indirect and direct costs will be analyzed every year.

Inclusion Criteria:

• COPD patients on necessity of long-term oxygen therapy
• Patients treated by LTOT, with or without clinically fulfilled criteria for LTOT, with PaO2<55mmHg or less at rest or during sleeping or less during exercise, if supplemental oxygen is demonstrated to improve the exercise-associated hypoxia. Patients with PaO2 56-59mmHg if they also have dependent edema, pulmonary hypertension or hematocrit higher than 56%
• Patient clinically stable
• Patient with oxygen device of ANTADIR network
• Oral and written consent

Exclusion Criteria:

• Patient with obstructive sleep apnea or overlap syndrome
• Patient with non invasive ventilation
• Patient with evolutive cancer.
• Inability to complete questionnaires
• Inability to attend outpatient clinic

COPD patients on necessity of long-term oxygen therapy