Cardiovascular disease is the leading cause of death worldwide, claiming an estimated 17.9 million lives each year. Identifying one’s risk for cardiovascular disease is a crucial step toward implementing appropriate preventative measures.
One of the key ways health care providers measure a person’s risk for cardiovascular disease is through a blood test called a lipid panel or lipid profile. This test shows the levels of beneficial and harmful lipids (or fats) that are present in the bloodstream. Generally, the higher the amount of “bad” cholesterol, the higher a person’s risk of developing heart disease.
However, research suggests that a specific protein found in the “bad” cholesterol, called Apolipoprotein B, is actually a more reliable indicator of overall cardiovascular disease risk compared to a standard lipid panel.
What Is Apo B?
Apolipoprotein B, also known as Apo B, is a protein found in low-density lipoprotein (LDL) cholesterol. Its primary function is to transfer lipids into the bloodstream.
This mechanism is particularly harmful because LDL molecules that contain Apo B are able to penetrate artery walls, leading to plaque buildup within the arteries. Over time, the buildup of plaque can lead to arterial damage and/or blockage, increasing the risk of heart disease, heart attack, and stroke.
Normal Apo B levels range from 60–133 mg/dL depending on the person’s biological sex. An Apo B level greater than 130 mg/dL typically indicates a higher risk of heart disease.
How Does an Apo B Test Predict Cardiovascular Disease Risk?
Research suggests that Apo B testing is a more accurate predictor of cardiovascular disease risk than a standard lipid panel.
A standard lipid panel includes:
- Total cholesterol. This is the sum total of the cholesterol content found in a person’s blood.
- Low-density lipoprotein (LDL) cholesterol. This is known as “bad” cholesterol. Too much LDL cholesterol can cause the buildup of fatty plaque deposits in the arteries, which reduces blood flow and leads to blockages.
- High-density lipoprotein (HDL) cholesterol. This is known as “good” cholesterol. It helps carry LDL cholesterol away from the arteries, thus preventing plaque buildup.
- Triglycerides. This is a type of fat in the blood created when the body converts calories it doesn’t need into fat cells.
Traditionally, health care providers would use the results of a lipid panel, particularly total cholesterol and LDL cholesterol levels, to determine a person’s risk of heart disease. However, recent research indicates that measuring Apo B levels can provide an even more accurate picture of a person’s heart health.
The reason? LDL levels are not a consistently reliable predictor of heart disease because LDL particles vary in size and density. However, every LDL particle contains just one Apo B molecule, providing a more accurate reflection of the number of LDL particles in the blood.
Why Is Getting an Apo B Test Important?
Apo B testing can provide a more comprehensive evaluation of a person’s cardiovascular health. Higher levels of Apo B in the blood have been shown to increase the risk of heart attack, stroke, and diabetes.
Apo B testing is especially important for people who have other risks for heart disease, such as insulin resistance, Type 2 diabetes, obesity, elevated triglycerides, metabolic syndrome, and/or family history of heart disease.
Measuring Apo B levels is not only useful for prevention, it is also helpful when cardiovascular disease is already present. For example, Apo B testing can help guide treatment options more accurately and be used to determine the efficacy of the current treatment regimen. Thus, having Apo B results can help your health care provider make necessary adjustments to your medications with more confidence.
Are There Any Disadvantages to the Apo B Test?
One of the main disadvantages of the Apo B test is cost. It is often not covered by insurance, so patients must pay out of pocket. It usually costs less than $100 at independent laboratories, but the upfront cost may not be affordable for some patients.
Another limitation is that certain medical conditions can skew Apo B test results. For example, hypothyroidism, nephrotic syndrome, or pregnancy can cause a person’s Apo B levels to be higher than normal and sepsis, liver disease, or hyperthyroidism can cause a person’s Apo B levels to be lower than normal. In these cases, Apo B may not be as reliable of an indicator of cardiovascular disease risk.
Medications can affect Apo B results, as well. Hormone drugs, beta-blockers, diuretics, and statins all have the potential to alter Apo B levels.
While many factors can contribute to a person’s heart disease risk, it is clear that Apo B measurement is particularly useful during the evaluation process. Recent research findings strongly suggest that Apo B testing should become a standard of care, along with a lipid panel, when assessing a person’s risk for cardiovascular disease or when determining the most effective treatment plan for those already diagnosed.
