Small, dense low density lipoproteins, the insulin resistance syndrome and noninsulin-dependent diabetes.

The role of small, dense LDL as a risk factor for coronary heart disease is becoming well established. Several atherogenic mechanisms have been proposed to explain this relationship, including the association of small, dense LDL with the insulin resistance syndrome. A variety of studies, including large epidemiologic investigations, have now demonstrated that a predominance of small, dense LDL is one of the constellation of interrelated risk factors that characterize the insulin resistance syndrome. Recent results using a multivariate factor analysis approach have also shown that this set of risk factors can be simplified into three or four uncorrelated components that may provide new insights into the mechanisms underlying the syndrome and its association with disease. Furthermore, a number of cross-sectional studies and one prospective study have shown that small, dense LDL is a risk factor for noninsulin-dependent diabetes itself, and that this association may also be attributable to the insulin resistance syndrome.