[Hypertriglyceridemia: danger for the arteries]

Abstract

AN INDEPENDENT RISK FACTOR: Although debate continues on the epidemiological impact, all surveys report that elevated serum triglyceride is an important risk factor in one-way analysis. More recent case-control studies in patients with premature coronary artery disease have shown that total triglyceride and VLDL levels discriminate better between subjects with and without coronary artery disease. Angiographic studies demonstrate that elevated serum triglyceride is found in coronary artery disease patients and that elevated VLDL or IDL is associated with severity. This relationship is persistently found when the serum cholesterol is taken into consideration but is no longer significant in most of the multivariate analyses. A recent meta-analysis is however in favor of an independent role for triglycerides, particularly in women. Two prospective studies published in 1998 confirmed that hypertriglyceridemia is an independent risk factor. VARIABLE IMPACT: Hypertriglyceridemia is a heterogeneous anomaly, not only due to different underlying pathophysiological mechanisms, but also in terms of cardiovascular risk. In familial hypertriglyceridemia, cardiovascular risk is apparently only moderately affected. Inversely, in combined familial hypertriglyceridemia and hyperapobetalipoproteinemia, the risk of premature cardiovascular disease is increased. ATHEROGENIC EFFECT: Unlike large VLDL rich in triglycerides, small VLDL rich in cholesterol ester have a strong atherogenic potential. Likewise, remnants are potentially atherogenic due to their relatively high cholesterol ester component and their accumulation on the arterial wall (Zilversmit postprandial atherogenesis theory). INCREASED RISK: The triglyceride-related risk is partly the consequence of frequently associated changes in lipoprotein distribution (lower HDL cholesterol, principal consequence of hypertriglyceridemia, elevation of small dense more readily oxidizable LDL) and hemostasis disorders (increased factor VIIc and PAI-1). In addition, hypertriglyceridemia is often found with other cardiovascular risk factors, particularly it readily occurs in insulin resistance syndromes.