Increased sympathetic activity, repetitive rises in blood pressure and apnea-induced stress in OSA may also contribute as a trigger to release several prohormones, such as the pro-atrial natriuretic peptide (proANP), the pro-adrenomedullin (proADM) and the pro-arginine vasopressin (proAVP or copeptin) [4, 5]. This evidence concerns the gene AVP and obstructive sleep apnea syndrome.