LDL particles can be separated on the basis of size and density into several different subclasses, as illustrated here. Small dense, triglyceride-rich LDL are believed to be more atherogenic than the large buoyant variety. A predominance of small LDL is referred to as the pattern B phenotype. Pattern B phenotype is one manifestation of what has been termed the Atherogenic Lipid Profile, a Mendelian-dominant inherited condition which also includes low levels of HDL-C, raised triglycerides, and insulin resistance. The presence of the pattern B phenotype increases the risk for clinical coronary heart disease by several fold. Niacin, fibrates, and bile-acid binding resins (but not statins) can cause favorable shifts in the LDL particle size subclass distribution from small towards large.