Abstract 13452: Serum Apolipoprotein B-48 Levels Are Significantly Correlated with Plaque Score of Carotid Arteries

Introduction: Fasting hypertriglyceridemia is a “residual risk” factor for atherosclerotic cardiovascular diseases and related to postprandial hypertriglyceridemia (PHTG). Intestine-derived lipoproteins such as chylomicrons and chylomicron remnants (CM-Rs), which contain one apolipoprotein(apo) B-48 molecule per one particle, are accumulated in patients with PHTG. Basic studies showed that CM-R had an atherogenic nature and apoB-48 molecule was observed in atherosclerotic plaque twice as many as apoB-100 molecule histologically. We established a CLEIA for measuring serum apoB-48 concentrations and reported that high apoB-48 concentrations correlated with the prevalence of dyslipidemia, diabetes mellitus, metabolic syndrome, chronic kidney disease and coronary heart disease. Hypothesis: We investigated whether serum apoB-48 concentration correlated with subclinical carotid atherosclerosis. Methods: A total of 163 subjects who received ultrasonography of carotid arteries in Osaka University were enrolled. Blood pressure (BP) at the supine position and serum concentrations of apoB-48, plasma glucose, HbA1c, TC, TG HDL-C and LDL-C were measured. Intima-media thickness (IMT) of carotid arteries was measured and plaque score (PS) were calculated in all subjects. Results: All subjects were classified into 4 groups by apoB-48 concentration quartiles: 1st (0-2.2 μg/mL, n=41), 2nd (2.3-3.5 μg/mL, n=39), 3rd (3.6-6.7 μg/mL, n=42) and 4th quartile (≧6.8 μg/mL, n=41), respectively. TG concentrations, prevalence of high BMI (≧25), max-IMT and PS were increased as apoB-48 concentrations were increased. Max-IMT and PS had significant correlations with age, eGFR, systolic BP, log-TG and log-apoB-48 levels and a multiple regression analysis indicated that the age, eGFR, and log-apoB-48 concentrations (p<0.05) were a significant determinant of an increased max-IMT and PS. In subjects whose TG concentrations were <150 mg/dL, max-IMT and PS were significantly higher in subjects of the 4th quartile than those of other quartiles. Conclusions: High serum apoB-48 concentrations strongly correlated with increased max-IMT and PS, indicating that the accumulated CM-Rs might be one of the increased risk for subclinical carotid atherosclerosis.