Mild-to-moderate hypertriglyceridemia in young men is associated with endothelial dysfunction and increased plasma concentrations of asymmetric dimethylarginine

OBJECTIVES The aim of this study was to investigate endothelial function an d common carotid intima-media thickness (IMT) in healthy young men with mil d-to-moderate hypertriglyceridemia. Plasma asymmetric dimethylarginine (ADM A), an endogenous nitric oxide synthase inhibitor, was measured to further elucidate the mechanisms involved. BACKGROUND Hypertriglyceridemia is a risk factor for coronary heart disease although the mechanisms behind the increased risk remain to be defined. Ac ute elevation of plasma triglycerides induced by an intravenous fat load is associated with impaired endothelial function. The results of studies exam ining acute effects induced by a high-fat meal or effects of chronic hypert riglyceridemia on endothelial function are more inconsistent. METHODS Flow-mediated vasodilation and nitroglycerin-induced vasodilation o f the brachial artery and common carotid IMT were measured noninvasively by ultrasound technique in 15 hypertriglyceridemic (HTC) subjects and 15 matc hed controls, mean age 34 years. Plasma concentrations of ADMA were measure d by high-performance liquid chromatography. RESULTS Flow-mediated vasodilation was decreased in the HTG group (p < 0.00 01), whereas nitroglycerin-induced vasodilation and carotid IMT did not dif fer significantly. Asymmetric dimethylarginine concentrations were higher i n the HTG group (p < 0.05). CONCLUSIONS Hypertriglyceridemia in young men is associated with endothelia l dysfunction and increased plasma concentration of ADMA but not with incre ased IMT of the common carotid artery. The corollary is that chronic hypert riglyceridemia results in endothelial dysfunction, possibly due to increase d ADR IA concentration, and that endothelial dysfunction might precede incr eased IMT among the early manifestations of atherosclerosis. (J Am Coil Car diol 2001; 38:111-6) (C) 2001 by the American College of Cardiology.