The potential of serum amyloid A-LDL as a novel biomarker for cardiovascular disease risk

While oxidative modification of LDL, a crucial step in atherogenesis, occurs in the arterial subintimal space and oxidized LDL (oxLDL) is observed chiefly in arterial lesions, oxLDL has also been shown to exist in the circulation, where it can become a surrogate biomarker of cardiovascular disease. The serum amyloid A-LDL (SAA-LDL) complex is currently considered to be a novel oxLDL marker in a broad sense. There have been several reports using SAA-LDL measurements in human subjects with lipid disorders, the metabolic syndrome and coronary artery disease. These reports have shown that there are higher circulating SAA-LDL levels in the aforementioned disease status and that a reduction in the levels of SAA-LDL can be achieved by intervention treatments including lifestyle modifications and drugs such as highly purified eicosapentaenoic acid. Data also suggest a prognostic value of SAA-LDL on cardiac events in patients with coronary artery disease. This article summarizes the current clinical data that indicate the usefulness of SAA-LDL measurements for understanding the pathophysiology of and assessing the risk of cardiovascular disease development.