Objective: To provide an overview of the relationship between low-density lipoprotein (LDL) density and coronary artery disease and to examine this relationship in terms of lipid peroxidation and the atherogenic remnant hypothesis.
Data sources: English-language studies and reviews pertaining to LDL composition and size were identified through a MEDLINE search and reference citations.
Study selection: Clinical studies on the following topics were critically reviewed: (1) the association between LDL density and coronary artery disease, (2) the relationship between LDL density and the levels and composition of other lipoproteins, and (3) the influence of environmental and genetic factors on LDL density.
Data synthesis: Low-density lipoprotein is a heterogeneous lipoprotein containing many subpopulations identifiable on the basis of density and size. There is an increased prevalence of small, dense LDL particles in coronary artery disease and conditions commonly associated with atherogenesis, such as non-insulin-dependent diabetes mellitus and familial combined hyperlipidemia. Exercise, visceral fat accumulation, and diet influence LDL density. In comparison with buoyant LDL, dense LDL is associated with a more atherogenic type of lipoprotein profile. An important relationship exists between the triglyceride level and the formation of LDL subpopulations.
Conclusion: Unraveling the connection between dense LDL and atherogenesis should provide important insights into the basic mechanisms underlying atherogenesis.