APOB and endothelial dysfunction: Previous studies have suggested that a high apo B/apo A1 ratio strongly correlates with pathophysiological markers of atherosclerosis defined by coronary angiography [8, 20], and calcium scores of the coronary arteries [21], and by ultrasound techniques such as the thickness of carotid arteries [16, 22, 23], endothelial dysfunction [24] and existence of femoral plaques [25].