Increased ApoB in small dense LDL particles predicts premature coronary artery disease.

The relation between plasma lipoproteins and atherosclerosis has evolved over the past fifty years. Serum cholesterol levels were shown to be associated with coronary artery disease (CAD) in familial hypercholesterolemia in the early 20 century (see Frederickson1). This cholesterol was determined to be in a particular lipoprotein class2 now termed low-density lipoprotein (LDL) cholesterol.3 LDL cholesterol has been shown to predict premature CAD in many studies,4 and a reduction in LDL cholesterol with statin therapy has been shown to decrease CAD events by up to 50% in primary5 and in secondary6 intervention trials. The National Cholesterol Education Program Adult Treatment Panel7 initially based recommendations for therapy to prevent CAD on LDL cholesterol levels. Later the measurement of HDL cholesterol was added to estimate risk.8