Investigation of Serum Oxidized Low-Density Lipoprotein IgG Levels in Patients with Angiographically Defined Coronary Artery Disease

It has been suggested that antioxidized low-density lipoprotein (anti-oxLDL) antibodies play a role in the pathogenesis of atherosclerosis. The aim of this study was to measure serum ox-LDL IgG levels in 31 patients with angiographically defined coronary artery disease (CAD) (≥50% stenosis in at least one major coronary artery; CAD(+) group) and compare these levels with those of 32 subjects with <50% coronary stenosis (CAD(-) group) and 24 healthy age- and sex-matched controls using ELISA. We did not find any significant difference between CAD(+), CAD(-), and control groups in regard to oxLDL IgG levels (P = 0.83). Serum oxLDL IgG levels did not differ between 1VD (one vessel disease), 2VD (2 vessels disease), and 3VD (3 vessels disease) subgroups of CAD(+) patients (P = 0.20). Serum anti-oxLDL titers were only significantly correlated with LDL-C in the CAD(+) group (P < 0.05) and waist and hip circumference (P < 0.05 and P < 0.01, resp.) in the CAD(-) group. In stepwise regression analysis, none of the conventional cardiovascular risk factors was associated with serum ox-LDL IgG levels. The present results suggest that serum levels of ox-LDL IgG are neither associated with the presence and severity of CAD nor with the conventional cardiovascular risk factors.