This test is suitable if you:

• Would like to assess your risk of developing CVD
• Have normal or slightly elevated levels of LDL cholesterol
• Are at risk of CVD and would like to learn more
• Have a family history of CVD, hyperlipidemia (high cholesterol and triglycerides) or diabetes
• Would like to evaluate the effectiveness of lifestyle changes, such as dietary modifications and exercise, or medications at lowering cholesterol levels.

This test is not suitable if you:

• Have a history of liver or kidney disease or other conditions that can affect lipid metabolism and ApoB levels in the blood
• Are taking medications that can affect lipid metabolism, such as steroids or thyroid medications
• Are pregnant or breastfeeding, as pregnancy and lactation can affect lipid metabolism and ApoB levels

First, it’s necessary to understand lipid metabolism and cholesterol. Cholesterol is a type of fat that is essential for human life and used by cells as a building block for hormones and a structural material (cell membranes, nerve cell insulation). Although every cell can create its own cholesterol, it is mostly produced by the intestines and liver. Transporting cholesterol through the bloodstream poses a problem because it is hydrophobic, it does not like water, and thus it does not dissolve in blood. To solve this issue, cholesterol is enclosed by a hydrophilic shell called a lipoprotein to allow it to travel in small particles.

Different types of lipoproteins transform into each other as they release triglycerides. Very Low-Density Lipoprotein (VLDL) is the initial molecule in this series. VLDL is created when the liver bundles cholesterol with triglycerides into a protein-wrapped molecule that floats in the bloodstream. VLDLs release triglycerides into cells that can store them or use them for immediate energy. After losing some mass, VLDLs become Intermediate Density Lipoproteins (IDL), which return to the liver and removes about half from circulation. The remaining IDLs undergo hydrolysis and become Low-Density Lipoproteins (LDL) that carry a high concentration of cholesterol. LDLs circulate until they encounter a cell with an LDL receptor, at which point they are absorbed and broken down. When stored cholesterol passes a certain threshold, the cell slows its production of cholesterol and new LDL receptors, making it harder for LDL particles to deposit cholesterol and raising circulating LDL levels. Lipoprotein(a) or Lp(a) is a variant of LDL with an unknown biological purpose but may aid in wound healing and tissue repair.

The lipoproteins VLDL, IDL, LDL, and Lp(a) are all atherogenic and can cause serious cardiovascular disease. LDL is often referred to as “bad cholesterol” due to being the most abundant and atherogenic. When lipoproteins breach the walls of arteries, they start an inflammatory process, attracting macrophages to clear the waste. When there is too much cholesterol to clear, the macrophages are overwhelmed and can become “foam cells”, accumulate and cause build up arterial plaques. Eventually, these plaques can block blood vessels and lead to heart attacks or strokes. Lp(a) can accelerate this process by increasing inflammation. On the other hand, HDL, often referred to as “good cholesterol”, is not atherogenic and does not carry an ApoB protein. This is useful because the ApoB Tests can track atherogenic lipoproteins without including neutral or potentially beneficial HDL particles.

The ApoB Test can help in assessing a person’s risk for atherosclerosis and heart disease. Research has shown that ApoB is a better indicator of risk of developing CVD than LDL cholesterol.

There are often no signs or symptoms associated with high cholesterol or ApoB. However, it can significantly raise the risk or a heart attack or stroke. A blood test is the sole definitive method of knowing whether a person has high levels of cholesterol or ApoB.

Some people may experience symptoms related to cardiovascular disease, which can be caused by high cholesterol or ApoB. If you are experiencing any of these symptoms, SEEK MEDICAL ASSISTANCE IMMEDIATELY:

• Shortness of breath
• Chest pain or discomfort
• Pain or weakness in one or both arms
• Pain in the back, neck, jaw, or stomach
• Difficulty speaking
• Vision problems
• Dizziness or lightheadedness
• Symptoms associated with stroke such as face drooping, numbness, or confusion

The ApoB Test is available for anyone over the age of 18 who wishes to measure their ApoB to evaluate their risk of CVD.

No special preparation is needed for this test. However, since this test is often performed with tests that require fasting, such as LDL, HDL cholesterol and triglycerides, fasting may be required for at least 12 hours.

Your test results will be available in the 1DROP App and patient portal on the website, tablet or computer. You will receive a comprehensive and easy-to-understand report. You will be alerted if your results are outside the normal ranges.

In general, a lower ApoB level is considered beneficial, but there is still debate on the ideal cutoff point for determining risk of CVD.

The clinical guidelines of the American College of Cardiology and the American Heart Association consider ApoB above 130 mg/dL a “risk-enhancing factor” for atherosclerotic cardiovascular disease. Some groups have set more aggressive ApoB targets for people who are at a higher risk of developing heart disease. For example, the American Diabetes Association and the American College of Cardiology Foundation recommend an ApoB target of less than 90 mg/dL for people at risk of heart disease (diabetes). For those who are at even higher risk, such as those who already have heart disease, the recommendation is an even lower target of less than 80 mg/dL. Medscape recommends a ceiling of 130 mg/dL for low-risk patients, 110 mg/dL for moderate-risk patients, and 90 mg/dL for high-risk patients.