Platelet Activation and Circadian Rhythms of Clotting-Fibrinolysis Factors in Patients With Sleep Apnea Syndrome. Implications in the Precipitation of Cardiovascular Events

The hypothesis of the study is the following: Patients with sleep apnea-hypopnea syndrome have higher risk of cardiovascular mortality during the night.

Respiratory alterations (hypoxia, hypoxia- reoxygenation) that these patients suffer during the sleep may induce modifications in platelet function, clotting-fibrinolysis factors and endothelial function, that may accelerate cardiovascular events during the night

DESIGN: Prospective and controlled study

METHODS: 20 SAHS patients and 20 controls will be studied. The study includes:

a) medical history; b) anthropometric variables (weight, height, body mass index, waist-hip ratio); c) sleepiness tested by Epworth scale; d) conventional polysomnography (PSG); e) testing every 4 hours for a 24 hours period: clotting-fibrinolysis factors (factor V, VII, VIII; C and S protein, plasminogen tissular activator (t-PA) and inhibitor of plasminogen activator (PAI-1); platelet activation markers (CD62, CD63 and GPIIb/IIIa) and endothelial dysfunction markers (endothelins, nitrites/nitrates and asymmetrical dimethyl-arginine); f) basic biochemical profile and hemogram. Patients will be revaluated after 6 months of CPAP treatment.