Recent data suggest that some risk factors for atherosclerosis and platelet aggregation (i.e., brain-derived neurotrophic factor (BDNF), sCD40L (soluble CD40 ligand), serpin E1/PAI I (endothelial plasminogen activator inhibitor), and vascular endothelial growth factor (VEGFO)) may be involved in the underlying processes of idiopathic headaches [21,22,23,24,25,26,27,28,29,30]. This evidence concerns the gene CD40LG and atherosclerosis.