Utilizing Apolipoprotein B in Cardiovascular Risk Assessment

QUEST WEBINAR:

Utilizing Apolipoprotein B in Cardiovascular Risk Assessment - Transcript

Presenter: Maeson Latsko

[00:00:00] Hello. Today, we will be discussing the utilization of apolipoprotein B for cardiovascular risk assessment. I'm Dr. Maeson Latsko, Clinical Specialist for Quest's Cardiometabolic Center of Excellence at Cleveland Heart Lab.

[00:00:13] Cardiovascular disease is the number one killer of men and women, and claims more lives than all cancers combined. Yet risk for cardiovascular disease is still largely under identified. In fact, the first sign and symptom of disease is death in 64 percent of women and 50 percent of men. LDL cholesterol, or LDL C, is commonly used as an indicator to identify risk and determine treatment initiation, and still 50 percent of patients hospitalized with coronary artery disease have normal LDL C levels, while 50 percent of young adults were misclassified as low risk just prior to their first coronary event. These findings suggest that our current toolkit misses risk in many patients.

[00:00:59] Individuals with similar amounts of LDL cholesterol can have different levels of cardiovascular risk. It is the lipoprotein particles that can get trapped in the artery wall and lead to atherosclerotic buildup.

[00:01:12] The more particles present, the higher the likelihood of infiltration and retention in the blood vessel wall, promoting atherogenic progression.

[00:01:21] A lipid panel measures the concentration of lipids such as cholesterol and triglycerides present in an individual.

[00:01:28] However, cholesterol and triglycerides are hydrophobic and cannot mix with blood. Lipids are packaged in the lipoprotein particles pictured here. Triglycerides and cholesterol are contained within a phospholipid shell that allows the lipid to be transported throughout the body.

[00:01:44] Apolipoprotein B or apoB is a protein that is attached to each cholesterol delivering and potentially atherogenic particle ApoB is the primary apolipoprotein on all non HDL particles. Apolipoproteins serve as structural components of lipoprotein particles and act as ligands

[00:02:04] to bind LDL receptors. Each atherogenic particle, or non HDL particle, carries exactly one ApoB molecule on it. Thus, ApoB levels correspond to the total number of atherogenic particles in circulation.

[00:02:20] Having high levels of ApoB can lead to an increased risk for cardiovascular events and death. And this is particularly relevant when an individual has a higher number of particles or a higher ApoB level compared to what is expected based on their LDLC values alone. This is a concept called discordance.

[00:02:38] let's say we have a patient with an LDLC value of 100 milligrams per deciliter. That means that they fall within the 20th percentile for LDLC. If their ApoB is 78 mg per deciliter, that means that they do not show discordance. Both values fall within the 20th percentile.

[00:02:56] However, if a patient has an LDL C value of 100 mg per deciliter, but an ApoB value of 103 mg per deciliter, their LDL C falls within the 20th percentile, while their APO B falls within the 60th percentile. This means that cholesterol is not packaged efficiently. And there significantly more particles needed to transport LDL cholesterol. These particles are small, dense, and more atherogenic. Given that risk tracks with particle count and quality, this person is at greater risk for cardiovascular disease and events.

[00:03:32] So what conditions put patients at risk for having increased particles or discordance? Various conditions can lead to an increased number of particles, often driven by metabolic dysfunction, which is rooted in insulin resistance. These conditions include obesity, metabolic syndrome, diabetes, and hypertriglyceridemia. Elevated lipid particles, especially in relation to LDL C values, can be seen in patients who are secondary prevention or on lipid lowering therapies, which can decrease LDL C more significantly than ApoB.

[00:04:04] ApoB outperforms LDL C and non HDL C as a predictor of cardiovascular disease events. This is particularly relevant in individuals who show discordance, indicating that LDL C may underestimate the risk in these individuals.

[00:04:20] Recent data confirms that ApoB can identify individuals with a 50 percent greater risk for myocardial infarction beyond what is expected based on LDL C values alone.

[00:04:30] Additionally, ApoB levels are associated with residual cardiovascular risk and all cause mortality in patients on statin therapy.

[00:04:39] For these reasons, ApoB has been recognized by professional societies, including the American Heart Association, the American College of Cardiology, the American Association of Clinical Endocrinology, the National Lipid Association, the European Society of Cardiology, and others.

[00:04:54] Each societal recommendation highlights ApoB as the preferred measure for cardiovascular risk when testing is available, particularly in individuals with a borderline to high 10 year ASCVD risk or heightened risk for metabolic dysfunction and those syndromes that leave a patient at greater risk for discordance, such as insulin resistance, high triglycerides, obesity, and type 2 diabetes.

[00:05:16] Today, we took a deep dive into the strength of ApoB in accurately predicting lipid driven cardiovascular risk. Cardiovascular disease is multifaceted, and can be caused by an interplay between metabolic dysfunction

[00:05:29] which can drive lipid driven risk and lead to Increased particles that are small, dense, and more atherogenic, contributing to vascular inflammation. with the utility of cutting edge technology to provide a comprehensive assessment, we aim to create a healthier world, one life at a time.

[00:05:46] The following order information can be utilized to order ApoB and related tests through Quest Diagnostics Center of Excellence at Cleveland Heart Lab.

[00:05:55] Thank you.