ApoB: Another look at heart disease risk
There are many ways to check for cholesterol and other unhealthy fats in the blood. You may be familiar with LDL-cholesterol, HDL-cholesterol, triglycerides and total cholesterol. These are levels checked in a standard lipid panel, or cholesterol panel, taken from a simple blood test. The results of a lipid panel can help determine your overall risk for heart disease. This test is recommended at least every five years for adults, with more frequent testing if needed.
For some adults, it can also be helpful to add a test for apolipoprotein B, or ApoB. ApoB is a protein found on the particles that can deposit cholesterol in artery walls. Your ApoB level shows the total number of atherogenic lipoprotein particles circulating in the blood. Over time, these particles can cause the buildup of fatty plaque in the arteries.
Another way to think about this, according to Dr. Michael Shapiro, a professor of cardiovascular medicine at Wake Forest University School of Medicine, is through a freeway traffic analogy. A standard lipid panel is similar to counting the number of passengers on the road. ApoB is like counting the number of cars. The LDL-cholesterol value tells you how much cholesterol is being transported in the cars through the bloodstream.
ApoB estimates how many LDL particles are actually carrying that cholesterol, and therefore how many vehicles are crowding the highway and contributing to plaque buildup. “What causes traffic?” he said. “Is it too many passengers or too many cars? It’s too many cars. That’s ApoB.”
This difference matters because two people can have the same LDL-cholesterol level but a different number of cholesterol-carrying particles. In some cases, LDL-cholesterol may appear to be at a healthy level while ApoB may be elevated. When that happens, a standard lipid panel may not fully show a person’s risk for heart disease.
Testing for ApoB can be especially helpful for people with high triglycerides, metabolic syndrome or diabetes. These conditions can increase the number of harmful particles in the blood even when LDL-cholesterol levels look normal. An ApoB test can give a clearer picture of heart disease risk and help health care professionals guide treatment if needed.
Talk with your health care professional about which cholesterol blood tests might be right for you.
