The study aims to observe the short term effect (3-month) of sleep disordered breathing (SDB) on cardiovascular parameters, heart rate variability, endothelial function and surrogate markers of atherosclerosis after acute cerebrovascular events (ACE). The long-term effect (6-24-month) of Continuous Positive Airway Pressure (CPAP) on clinical vascular outcome, cardiovascular parameters, evolution of surrogate of atherosclerosis heart rate variability and endothelial function after ACE is observed over 24 months. A preventive effect of CPAP therapy on cerebro-vascular events in patients with moderate-severe obstructive SDB without sleepiness after ictus or transient ischaemic attack will be evaluated.