Abstract 12939: Erythrocyte-Bound Apolipoprotein B may be a Protective Factor of Clinical and Subclinical Atherosclerosis
Introduction: Preliminary data suggest that erythrocyte-bound apolipoprotein (apo) B (ery-apoB) may be associated with reduced cardiovascular risk. The association between ery-apoB and cardiovascular disease (CVD) and carotid intima media thickness (IMT) was assessed in an observational study.
Methods: Carotid IMT was measured in subjects with and without CVD. IMT >0.70 mm was considered increased. Next to standard lipid parameters, ery-apoB was measured by flow cytometry using polyclonal antibodies against apoB. Subjects with ery-apoB levels <0.20 a.u. were considered ery-apoB deficient.
Results: A total of 409 subjects were investigated of whom 264 showed a normal IMT (0.57±0.07 mm) and 145 an increased IMT (0.80±0.09 mm). Subjects with increased IMT were older (65.8±8.7 vs 54.2±11.7 years, P<0.001), were more frequently male (67 vs 48%, P<0.001) and obese (BMI of 27.9±4.6 vs 26.5±4.5 kg/m2, P<0.01). They had a higher incidence of CVD (65 vs 38%, P<0.001) and they used more often statin therapy (69 vs 43%, P<0.001). Erythrocyte count and plasma apoB were similar between the two groups. Ery-apoB was lower (0.89±0.83 a.u) in subjects with increased IMT compared to subjects with a normal IMT (1.16±0.92 a.u.; P=0.007). This difference remained significant (P<0.001) after adjustment for age, gender, CVD, BMI, HDL-C and type 2 diabetes mellitus. An inverse correlation existed between IMT and ery-apoB (Spearman’s r: -0.116, P=0.021). A total of 55 subjects (13.8%) was considered ery-apoB deficient. These subjects showed a higher leukocyte count (7.2±1.6 *109/l), lower HDL-C (1.26±0.36 mmol/l) and had a higher incidence of CVD (60.0%) than those with a higher ery-apoB (6.5±1.8 *109/l,1.41±0.42 mmol/l, 44.6%, respectively, each P<0.05). CVD risk was almost two-fold increased for ery-apoB deficient subjects (OR: 1.86; 95% CI 1.04-3.33).
Conclusion: Absence or very low levels of ery-apoB may be a novel biomarker for clinical and subclinical atherosclerosis.
- © 2012 by American Heart Association, Inc.