Effects of Home-based Pulmonary Rehabilitation in Patients With Severe or Very Severe Chronic Obstructive Pulmonary Disease (COPD)

Inclusion Criteria: * Severe COPD (FEV1/FVC \< 70% and FEV1 \< 50% pred.) associated to hypoxaemic chronic respiratory insufficiency (PaO2 \< 60mmHg) or * Very severe COPD (FEV1/FVC \< 70% and FEV1 \< 30% pred.) With the following characteristics: * no signs of lung restriction (TLC≥80%) * clinically stable for at least the last four weeks * MRC ≥ 2 * no participation to PR programmes in the last year FEV1= Forced expiratory volume in the 1st second FVC= Forced vital capacity TLC= Total Lung Capacity PaO2= Partial pressure of arterial oxygen Exclusion Criteria: * \- Muscular-skeletal impairment that could limit the patient's participation to the exercise programme; * Cognitive impairment that could limit the patient's participation to the activities of education and exercise, as assessed by the Mini Mental State (MMS) test \<26; * Malignancies