From the Guidelines
Apolipoprotein B (ApoB) is a protein that serves as a primary component of low-density lipoprotein (LDL) and very low-density lipoprotein (VLDL), making it a crucial marker for assessing cardiovascular disease risk, with optimal levels being <80 and <100 mg/dL for subjects with very high or high CVD risk, respectively, as suggested by the European guidelines on cardiovascular disease prevention in clinical practice 1. Apolipoprotein B plays a significant role in the transport of cholesterol and fat in the bloodstream, and its levels have been frequently measured in outcome studies in parallel with LDL cholesterol. According to the European guidelines 1, ApoB can be substituted for LDL cholesterol in risk assessment, but it does not add further to the risk assessment. The guidelines also suggest that ApoB is a similar risk marker to LDL cholesterol and a better index of the adequacy of LDL-lowering therapy. Some key points about ApoB include:
- It is the main apoprotein of atherogenic lipoproteins
- High levels of ApoB are associated with an increased risk of cardiovascular disease
- ApoB levels can provide valuable information about cardiovascular risk, especially in people with diabetes, metabolic syndrome, or those with normal LDL cholesterol but elevated triglycerides
- Measuring ApoB levels can offer more precise risk assessment than traditional cholesterol tests in certain individuals
- Laboratories could easily and inexpensively provide standardized measurements of ApoB, with less laboratory error compared to LDL cholesterol, particularly in patients with hypertriglyceridaemia 1.
From the Research
Definition and Role of Apolipoprotein B
- Apolipoprotein B (apoB) is a critical structural protein of atherogenic lipoproteins, including low-density lipoprotein (LDL) and very-low-density lipoprotein (VLDL) 2, 3, 4, 5.
- ApoB has two major isoforms: apoB48 and apoB100, with apoB48 found in chylomicrons and chylomicron remnants, and apoB100 found in VLDL, intermediate density lipoprotein, LDL, and lipoprotein(a) 4, 5.
Apolipoprotein B and Cardiovascular Disease
- ApoB is considered a more accurate measure of cardiovascular risk than LDL cholesterol or non-high-density lipoprotein cholesterol (non-HDL-C) 3, 5.
- The plasma apoB concentration is a direct measure of the number of circulating atherogenic lipoproteins, making it a valuable biomarker for cardiovascular disease risk assessment 3, 5.
- Studies have shown that apoB levels indicate the atherogenic particle concentration independent of the particle cholesterol content, which is variable 5.
Clinical Significance and Potential Therapeutic Target
- Despite strong evidence supporting the use of apoB as a therapeutic target, its adoption into routine clinical practice has been limited due to lack of consistent guidance for clinicians on how to interpret and apply apoB results 6.
- Ongoing discussions and research aim to establish evidence-guided apoB thresholds for use in cholesterol management and clinical care 6.
- ApoB measurement has been proposed as a potential tool to bridge the gap between evidence and clinical practice, providing a more accurate indicator of cardiovascular risk than traditional lipid profiles 6.