A life-saving number you’ve never heard of

Do you know your lipoprotein(a) score? It might be the life-saving number you’ve never heard of.

Lipoprotein(a), or serum lipoprotein(a), is usually referred to as Lp(a) or “LP little a,” by clinicians and is a type of low-density cholesterol that’s not measured in regular blood screenings. But the presence of it in your blood puts you at higher risk for vascular issues such as heart attacks and strokes, said John Hostetter, MD, FACC, a cardiologist with Cape Cod Healthcare Cardiovascular Center in Falmouth.

“It can cause plaque buildup, and it can also be a bit pro-inflammatory. And inflammation seems to increase risk,” Dr. Hostetter said.

Cholesterol travels through the blood on lipoproteins, consisting of protein and fat, according to the U.S. Center for Disease Control. The other more familiar lipoproteins are low-density lipoprotein (LDL), or so-called “bad” cholesterol,” which raises your risk for heart attack and stroke, and high-density lipoprotein (HDL), or “good cholesterol,” which absorbs fat from your bloodstream and takes it to the liver. Both of these are routinely tracked as part of the blood work done to check your cholesterol and triglycerides, another type of fat.

Like LDL-cholesterol, Lp(a)-cholesterol builds up in the walls of your blood vessels, the CDC says. These cholesterol deposits, or plaques, decrease blood flow to your heart, brain, kidneys, lungs, legs, and other body parts. Lp(a) also can encourage clotting, which may lead to blood vessel blockages; can spark inflammation, increasing the likelihood that plaques will rupture, causing heart attack or stroke; and can lead to aortic stenosis, or the narrowing of the aortic valve, the CDC says.

“In fact, there was a pediatric study in the last six months where they seemed to find a correlation between elevated Lp(a) in children and cardiac risks over time, meaning people who had an elevated level as a child seemed to be twice as likely to have vascular disease as they got older,” Dr. Hostetter said.

Testing Lp(a) Levels

LDL, HDL and triglyceride levels can change throughout life, based on diet, exercise and medications. But Lp(a) levels are genetic and tend to be stable throughout life. Or, as Dr. Hostetter put it, “It is what it is.” As many as 20 percent of people worldwide may have elevated levels, he said.

Currently, there’s no drug that specifically targets Lp(a), although there are trials in the works, he said.

In this country, Lp(a) is not routinely checked, Dr. Hostetter said. However, the American Heart Association says that because it raises cardiac risks, it’s reasonable to screen people between the ages of 40 and 75.

Dr. Hostetter believes it’s an underused test. It’s reasonable, he said, to screen people at least once in their lives, as recommended by the European Society of Cardiology, particularly those at low to moderate risk of cardiac issues who are not already being treated with diet, exercise and medications such as statins. While lifestyle and medication might not affect Lp(a), the more aggressive treatment of other dangerous risk factors could help prevent problems partly caused by it. Knowing the Lp(a) level can help the clinician and patient make decisions on how to try and control cholesterol or blood pressure that’s outside recommended norms, Dr. Hostetter said.

“Take somebody in their 50s who maybe has some high blood pressure but otherwise seems pretty healthy. If their Lp(a) number is low, that can be reassuring. And if it’s really high, it means we should really focus our attention on prevention for them,” he said. “If we lower the LDL, we think that moves the risk in the right direction. Or, we might be likely to target a little lower blood pressure.”

Finding out your Lp(a) can be motivating, even if there’s currently not much to be done about it specifically, he said.

“If it motivates patients to take care of themselves and stop smoking and lose 10 pounds and take a cholesterol medicine they were not eager for, it can be beneficial. It can focus our attention earlier and preventatively as opposed to waiting for somebody to have their first cardiac event.”