Metabolic Syndrome
There is little doubt that this syndrome taken in aggregate enhances the risk for CHD at any given LDL-cholesterol level. The lipid component of this condition consists of abnormal levels of triglycerides and apoB, small LDL particles, and low HDL-C. The metabolic syndrome and its associated risk factors have emerged as a coequal partner to cigarette smoking as contributors to premature CHD. In addition, the insulin resistance accompanying the metabolic syndrome is one of the underlying causes of type 2 diabetes. For these reasons, NCEP places increased emphasis on the metabolic syndrome as a risk enhancer. The root causes of the metabolic syndrome are overweight/obesity, physical inactivity, and genetic factors.
ApoB-100
ApoB is found in chylomicrons, VLDL, IDL, LDL, and Lp(a) particles. Since each of these particles contains a single apoB molecule, measurements of apoB represent the total burden of particles considered most atherogenic. Apolipoprotein B, or apo B, is a marker for all atherogenic lipoproteins. It has been proposed as an alternative to LDL cholesterol as a risk factor Limited epidemiological and clinical trial evidence supports its superiority over LDL cholesterol in risk prediction. Although LDL cholesterol and apolipoprotein B are highly correlated in persons with normal triglyceride levels, the apolipoprotein B level typically is disproportionately higher in persons with hypertriglyceridemia.
