Background: Several groups of patients at high risk for cardiovascular disease have been found to show an exaggerated postprandial hypertriglyceridemia. Postprandial lipemia (PPL) therefore has been implicated as a potential additional risk factor that has been evading us. The purpose of this study was to test the effect of high fasting high-density lipoprotein cholesterol (HDL-C) levels on PPL in postmenopausal females.
Methods: Oral fat tolerance test, as quantified by the areas under the curve (AUC) of triglyceride (TG) levels, was given to 3 groups: normal postmenopausal females (control), postmenopausal females with exceptionally high HDL-C and a familial history of longevity (longevity syndrome), and postmenopausal females that were heterozygotes of familial hypercholesterolemia (hFH) with exceptionally high HDL-C.
Results: The PPL was not different between the control and longevity syndrome groups but was significantly higher in the hFH group; AUC (SD), in mg/dl/h; 749 (195), 882 (278) and 1244 (497) respectively, p=0.002. In linear regression analysis only fasting TG levels were a significant predictor of the AUC (Coefficient B = 11.779, p < 0.001).
Conclusions: In subjects with longevity syndrome the PPL is similar to controls, which means that high fasting HDL-C has not any beneficial influence on PPL. The fasting TG concentration is the main determinant of PPL. Furthermore, postmenopausal females with hFH have higher TG response postprandially, even in the case of high fasting HDL-C. Whether there is a threshold below or above, where HDL-C becomes a significant independent determinant of PPL is a question to be answered by future research.