From the Guidelines
Patients with high Lipoprotein(a) (Lp(a)) levels should aim for an Apolipoprotein B (ApoB) level below 130 mg/dL to reduce their cardiovascular risk. According to the 2018 AHA/ACC/AACVPR/AAPA/ABC/ACPM/ADA/AGS/APhA/ASPC/NLA/PCNA guideline on the management of blood cholesterol, an ApoB level of 130 mg/dL or higher is considered a risk-enhancing factor for atherosclerotic cardiovascular disease (ASCVD) 1. This guideline suggests that patients with elevated Lp(a) levels, which are a risk-enhancing factor for ASCVD, may benefit from more aggressive lipid-lowering therapy to reduce their ApoB levels.
To achieve this target, a combination of lifestyle modifications and lipid-lowering medications is typically required. High-intensity statins like atorvastatin or rosuvastatin are usually the first-line therapy. If statins alone are insufficient, adding other lipid-lowering medications may be necessary. The goal is to reduce the ApoB level to below 130 mg/dL, which corresponds to an LDL-C level of 160 mg/dL or lower, as indicated in the guideline 1.
Key points to consider in managing patients with high Lp(a) levels include:
- Elevated Lp(a) is a risk-enhancing factor for ASCVD, especially at higher levels of Lp(a) 1
- ApoB level of 130 mg/dL or higher is considered a risk-enhancing factor for ASCVD 1
- Reducing ApoB levels to below 130 mg/dL may help counterbalance the additional cardiovascular risk associated with elevated Lp(a) levels
- A combination of lifestyle modifications and lipid-lowering medications is typically required to achieve this target.
From the Research
ApoB Levels in Patients with High Lp(a)
To determine the appropriate Apolipoprotein B (ApoB) level for patients with high Lipoprotein(a) (Lp(a)), several factors must be considered, including the patient's overall cardiovascular risk profile and the presence of other lipid abnormalities.
- The current consensus, as noted in 2, supports using an Lp(a) percentile greater than 75% for race and gender as a risk stratification tool to target more aggressive low-density lipoprotein cholesterol (LDL-C) or ApoB goals.
- However, there is no specific ApoB level recommended for patients with high Lp(a) in the provided studies.
- A study published in 3 demonstrated a particle-based approach to quantify the contribution of Lp(a) to all ApoB-containing particles, which may help in assessing the risk and guiding treatment.
- Another study, 4, discussed the utility of genetically predicted Lp(a) and ApoB levels for cardiovascular risk assessment, suggesting that polygenic risk scores could reduce the need for Lp(a) and ApoB measurements in some individuals.
- The effect of PCSK9 inhibition with alirocumab on Lp(a) levels was investigated in 5, showing a decrease in plasma Lp(a) concentration through a dual mechanism of action in statin-treated patients with very high ApoB concentrations.
- Additionally, research in 6 highlighted the importance of Lp-PLA₂-bound ApoB in hypercholesterolemic patients, indicating that the elevation of ApoB is primarily attributed to the relative increase of ApoB/Lp-PLA₂.
Key Considerations
- Patients with high Lp(a) levels should be assessed for their overall cardiovascular risk, considering factors such as family history, presence of other lipid abnormalities, and subclinical vascular disease.
- The decision to target more aggressive LDL-C or ApoB goals should be based on individual risk assessment, as suggested in 2.
- Further research is needed to establish specific ApoB level targets for patients with high Lp(a) and to fully understand the mechanisms by which Lp(a) contributes to cardiovascular risk.