From the Guidelines
Apolipoprotein B (ApoB) is a crucial marker for cardiovascular risk, and its levels should be managed to reduce the risk of cardiovascular disease, with target levels generally below 80-90 mg/dL for high-risk individuals. ApoB is the major apolipoprotein of the atherogenic lipoprotein families VLDL, IDL, and LDL, and its concentration is a good estimate of the number of these particles in plasma 1. The measurement of ApoB can provide a more accurate risk prediction than traditional lipid measurements like LDL cholesterol, especially in cases of high concentrations of small dense LDL.
Several studies have shown that ApoB is a strong predictor of cardiovascular risk, with some suggesting that it may be a better treatment target than LDL-C 1. However, recent data from a meta-analysis by the Emerging Risk Factor Collaboration indicate that ApoB does not provide any benefit beyond non-HDL-C or traditional lipid ratios 1. In contrast, another meta-analysis found that ApoB was superior as a marker of CV risk compared to LDL-C and non-HDL-C.
Key points to consider in the management of ApoB levels include:
- ApoB can be measured through a simple blood test, typically as part of an advanced lipid panel
- Target levels for ApoB are generally below 80-90 mg/dL for high-risk individuals, though optimal levels may vary based on individual risk factors
- Management of high ApoB levels typically involves lifestyle modifications (diet, exercise, weight management) and may include medications such as statins, ezetimibe, PCSK9 inhibitors, or bempedoic acid when appropriate
- Non-HDL cholesterol, which is highly correlated with ApoB levels, can be used as a surrogate marker for ApoB in clinical practice, with a target level of 130 mg/dL for persons with serum triglycerides greater than or equal to 200 mg/dL 1.
Overall, the management of ApoB levels is an important aspect of cardiovascular risk reduction, and healthcare providers should consider ApoB levels in the assessment and management of patients at high risk of cardiovascular disease.
From the Research
Apolipoprotein B as a Measure of Cardiovascular Risk
- Apolipoprotein B (apoB) is considered a more accurate measure of cardiovascular risk and a better guide to the adequacy of lipid lowering than low-density lipoprotein cholesterol (LDL-C) or non-high-density lipoprotein cholesterol (HDL-C) 2.
- The 2019 European Society of Cardiology/European Atherosclerosis Society Guidelines concluded that apoB can be measured more accurately than LDL-C or non-HDL-C 2.
Relationship between Apolipoprotein B and LDL-Cholesterol
- Studies have shown a degree of discordance between LDL-C and apoB levels among patients not receiving lipid-lowering therapy 3.
- The association between apoB and LDL-C is similar across different lipid-lowering treatment regimes, suggesting that the use of different lipid-lowering agents confers similar ability to predict apoB levels 3.
- After switching to ezetimibe/simvastatin or rosuvastatin, the LDL-C and non-HDL-C corresponding to apoB=0.9 g/L were closer to the more aggressive LDL-C and non-HDL-C goals 4.
Effects of Statins on Apolipoprotein B Metabolism
- Atorvastatin and simvastatin stimulate direct catabolism of large very low density lipoprotein (VLDL(1)) apoB and increase the fractional transfer rates of VLDL(1) to VLDL(2) and of VLDL(2) to intermediate density lipoprotein (IDL) 5.
- Both atorvastatin and simvastatin increase IDL apoB direct catabolism and enhance the fractional transfer rate for IDL to LDL conversion 5.
Association of Lowering Apolipoprotein B with Cardiovascular Outcomes
- A systematic review and meta-analysis of trials found that lowering apoB is associated with reduced cardiovascular outcomes across various lipid-lowering therapies 6.
- The relative risks of all-cause mortality and cardiovascular mortality were 0.95 and 0.93, respectively, for every 10 mg/dL decrease in apoB by all interventions combined 6.