Small Dense Low-density Lipoprotein and Cardiovascular Disease

Cardiovascular disease (CVD) is the leading cause of death worldwide and small dense low-density lipoprotein (sdLDL) has been suggested to be a potential risk factor for cardiovascular disease (CVD). We reviewed published studies on formation and measurement of sdLDL, as well as relationship between LDL subfractions and CVD. sdLDL particle formation is highly dependent on triglycerides (TG) levels, and the physicochemical properties of sdLDL particles provide a potential for increased atherogenicity. Various conditions (e.g. hypertriglyceridemia, diabetes mellitus, metabolic syndrome, chronic renal failure and HIV infections) with increased cardiometabolic risk are associated with increased sdLDLs. Most studies suggest that sdLDL particles are associated with increased prevalence of clinical and subclinical CVDs, as well as non-coronary forms of atherosclerosis. Moreover, LDL size seems to be an important determinant of the progression of CVD. Therapeutic modulation (mostly fibrates, but also some statins, as well as niacin and thiazolidinediones) of small LDL size, number and distribution may decrease CVD risk. However, no definitive causal relationship is yet established, probably due to the close association between sdLDL and triglycerides and other risk factors.