Association of Postprandial Triglyceride and Retinyl Palmitate Responses with Asymptomatic Carotid Artery Atherosclerosis in Middle-aged Men and Women: The Atherosclerosis Risk in Communities (ARIC) Study

Blood lipid alterations after a fatty meal may be atherogenic, but there is little information regarding their associations with disease independent of fasting lipids. Asymptomatic atherosclerosis cases (n=229) and 373 control subjects free of atherosclerosis, as defined by carotid intima-media thickness on ultrasound images, were given a fatty meal with vitamin A, followed by 3.5- and 8-hour measurements of triglycerides (TGs), TG-rich lipoprotein TGs, apoproteinB48, and retinyl palmitate. Among white men and women but not among blacks, case status was associated with greater postprandial responses of TGs and TG-rich lipoprotein TGs, but only in nonobese persons (body mass index <30 kg/m²). The associations were strong and significant after controlling for coronary risk factors (odds ratio, ≈2.0) and fasting TGs (odds ratio, 1.5). Associations with other postprandial lipid measurements did not persist after controlling for fasting lipids. Elevated postprandial TGs appear to be an independent risk factor for carotid intimai thickening in nonobese whites. The lack of such a relation in obese subjects and the lipid profile they manifest suggest that postprandial TGs must be accompanied by accumulation of TG-rich lipoprotein remnants to be atherogenic.