Meet Bad Cholesterol's Trouble-Making Sidekick

There's more to cholesterol levels than HDL and LDL: Meet lipoprotein(a), or Lp(a)

Imagine your cholesterol numbers as characters in the story of your heart health.

The villain — low-density lipoprotein (LDL) — sticks to arterial walls. It potentially restricts blood flow, leading to heart attacks and strokes. Meanwhile, the hero — high-density lipoprotein (HDL) — swoops in to save the day, carrying LDLs away from your arteries so they remain clear.

Now imagine the villain has a trouble-making sidekick called lipoprotein(a), or Lp(a) (it's pronounced "L P little a"). It clings to LDL and, in some people, can be found in high levels that heart experts now associate with the following health problems:

  • Increased risk of heart disease and heart attack
  • Stroke
  • Blood clots

While diet and exercise may help control run-of-the-mill LDL cholesterol, these healthy behaviors appear to have little impact on Lp(a). That's why doctors at Rush are looking at ways to protect their patients from the damaging effects of high levels of Lp(a) — and it starts with raising awareness about this little-known yet serious threat.

Are you at risk?

Research indicates that one in five people have high levels of Lp(a). It often passes from one generation to the next undetected. "Lp(a) can go undiagnosed because doctors don't routinely test for it when checking your cholesterol," says Annabelle Volgman, MD, cardiologist and director of the Rush Heart Center for Women. 

"In our practice, we'd see patients under 50 having heart attacks who didn't have significant risk factors and were baffled," Volgman says. "We wondered 'Why so young?' "

So Volgman and her team started performing advanced lipid testing to look for abnormalities. And they found that many of their patients had elevated Lp(a) levels. "In women we tested, more than 40 percent had high levels."

That's why Volgman advises keeping an eye out for important risk factors when it comes to Lp(a):

  • Family history of heart and circulatory diseases, especially at young age.
  • Heart attacks, strokes and blood clots with no known risk factors (smoking, high blood pressure, high LDL numbers, diabetes or obesity).
  • Race and ethnicity: South Asians and blacks appear more prone to have elevated Lp(a).
  • Perimenopause: As estrogen goes down, Lp(a) levels appear to go up, says Volgman.

If you have any of these risk factors, talk to your doctor about having a blood test for Lp(a) when testing cholesterol, Volgman says.

While diet and exercise may help control run-of-the-mill LDL cholesterol, these healthy behaviors appear to have little impact on Lp(a).

At risk? Consider testing for you and your family

Some doctors may be resistant to extra testing because there's currently no established treatment for lowering Lp(a) levels. But many, like Volgman, believe equipping patients and their doctors with this information can be incredibly valuable for these reasons:

  • Lowering your LDL cholesterol is known to decrease overall risk of heart events and can potentially decrease the bad effects of Lp(a).
  • Daily doses of baby aspirin can potentially reduce risk of blot clots, a problem linked to high Lp(a) levels.
  • By knowing your increased risk, you can make lifestyle changes to improve your overall health. Strong, healthy bodies are usually better able to recover from heart attacks and strokes.
  • You can share your test findings with family members who may also be affected by this hereditary condition. "Each child born to someone with high Lp(a) has a 50 percent chance of inheriting it," Volgman says. "Knowledge can empower your entire family."

While there aren't currently any medications that have the power to lower Lp(a), researchers are looking at new therapies to specifically target Lp(a) levels.

Until those are available, Volgman strongly encourages you to be the hero of your heart health story: If you have a family member who has suffered a heart attack, stroke or blood clots prior to age 50, talk to your doctor about Lp(a) blood testing.

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