We all know high cholesterol has the potential of increasing our risk of heart attack and stroke. Those who regularly see their doctor also probably get routine tests to determine their HDL (“good cholesterol”) and LDL (“bad cholesterol”). But did you know there might be more to the story?
HDL and LDL are lipoproteins and carry cholesterol through our bloodstream. However, there are other lipoproteins that many doctors don’t request on routine blood panels. It’s problematic because those numbers tell us things HDL and LDL alone can’t. As a result, some people incorrectly believe that since their cholesterol is at a healthy level, they don’t have to worry about hardening of the arteries.
Apolipoprotein B (apoB) is another important lipoprotein to measure. Multiple studies have shown that apoB levels provide a more accurate prediction for who is (and is not) at risk for heart disease and stroke. Unfortunately, not all doctors have adapted to ordering this test as a routine.
While LDL cholesterol levels are felt by the American Heart Association to be a reliable indicator for most people, there are cases where LDL is within a normal range but apoB levels are high. People then have heart attacks or strokes while thinking they are perfectly healthy. Fortunately, there are treatments and medications that can reduce your apoB and thereby reduce this risk. The catch is, you need to know your apoB is elevated. So, I recommend that you do your own research about apoB so you are comfortable requesting this test the next time you go in to see your internist or cardiologist. If they have already checked your apoB in the past and it was normal, that is great, but it can go up or down over time so a repeat test might be helpful to confirm that it is still normal.
Lipoprotein (a) (known as LP(a) or “LP little a”) is another lipoprotein that can predict the risk for cardiovascular disease. Your level of LP(a) is genetically determined and roughly static throughout a lifetime. Depending on the study you reference, LP(a) is elevated in 10 to 20% of the population., and you can have a high LP(a) but have low LDL cholesterol and even a low apoB. For example, professional tennis player Arthur Ashe was in great shape but had a heart attack at age 36. He had a high level of LP(a).
Unfortunately, there are no FDA approved treatments to lower LP(a). As a result, many doctors don’t order the test. But requesting it will provide peace of mind if your LP(a) is normal. Also, if you do have high LP(a), your doctor can help you maximally reduce your controllable risk factors, thereby lowering the overall danger of a heart attack or a stroke. Consider asking about these tests — the knowledge could be powerful and might save your life.