Alimentary lipemia, postprandial triglyceride-rich lipoproteins, and common carotid intima-media thickness in healthy, middle-aged men.

BACKGROUND Alimentary lipemia has been associated with coronary heart disease and common carotid artery intima-media thickness (IMT). This study was designed to investigate the relations of subclasses of postprandial triglyceride-rich lipoproteins (TRLs) with IMT. METHODS AND RESULTS Ninety-six healthy 50-year-old men with an apolipoprotein (apo) E3/E3 genotype underwent an oral fat tolerance test and B-mode carotid ultrasound examination. The apo B-48 and apo B-100 contents of each fraction of TRLs were determined as a measure of chylomicron remnant and VLDL particle concentrations. In the fasting state, LDL cholesterol (P<0.05) and basal proinsulin (P<0. 05) were significantly related to IMT, whereas HDL cholesterol, plasma triglycerides, and insulin were not. In the postprandial state, plasma triglycerides at 1 to 4 hours (P<0.01 at 2 hours), total triglyceride area under the curve (AUC) (P<0.05), incremental triglyceride AUC (P<0.01), and the large VLDL (Sf 60 to 400 apo B-100) concentration at 3 hours (P<0.05) were significantly related to IMT. Multivariate analyses showed that plasma triglycerides at 2 hours, LDL cholesterol, and basal proinsulin were consistently and independently related to IMT when cumulative tobacco consumption, alcohol intake, waist-to-hip circumference ratio, and systolic blood pressure were included as confounders. CONCLUSIONS These results provide further evidence for postprandial triglyceridemia as an independent risk factor for early atherosclerosis and also suggest that the postprandial triglyceridemia is a better predictor of IMT than particle concentrations of individual TRLs.