Remnant lipoproteins and atherosclerotic cardiovascular disease

Lipoproteins are one of the major risk factors for atherosclerotic cardiovascular disease (ASCVD), among which, low-density lipoprotein (LDL) particles have been definitively shown to be causally associated with the development of ASCVD. Additionally, the concept of remnant lipoproteins has emerged as lipoprotein metabolism has been fully investigated. The principal concept of this lipoprotein category is triglyceride-rich lipoproteins significantly increase at the postprandial state. Although there is no clear definition of remnant lipoproteins, they typically include chylomicron remnants, which are lipolyzed particles from chylomicron, as well as very low-density lipoprotein (VLDL) and intermediate-density lipoprotein (IDL) remnants that are lipolyzed particles from VLDL and IDL particles. However, the most important factor of these lipoproteins is such remnant lipoproteins seem to be causally associated with ASCVD, independent of LDL particles or LDL cholesterol. It has been challenging to assert a causal association of remnant lipoproteins and ASCVD; however, accumulated evidence from epidemiological studies, as well as recent Mendelian randomization studies from common and rare genetic variations strongly support this association. In this article, a basic explanation of lipoprotein metabolism is presented, including remnant lipoproteins and the important causal associations with ASCVD from a clinical point of view.