We’ve all heard the warnings about low-density lipoprotein (LDL), otherwise known as the “bad” cholesterol. It can greatly increase your risk for heart disease and stroke down the line.
But have you heard about lipoprotein(a), or Lp(a)? It’s another kind of bad cholesterol that’s not detected on regular cholesterol tests you get when you see your doctor.
What is it?
Lp(a) is a small protein that can travel in high levels through your bloodstream, accelerating the creation of harmful plaque that can block your arteries.
As it flows through, clumping together more and more plaque, your artery will gradually narrow, limiting the blood supply needed to pump to your heart and brain. This leads to an increased risk of blood clots, heart attack, stroke, and aortic stenosis.
Genetics is behind this kind of cholesterol — a potential risk factor for heart disease many people might not know they even have.
In fact, Lp(a) is the most prevalent genetic risk factor for coronary heart disease and aortic stenosis, wrote Sandra Revill Tremulis, founder of the Lipoprotein(a) Foundation, a nonprofit aiming to raise awareness about Lp(a) and the heart risks it can bring, in an email to Healthline.
For Tremulis, the drive to raise awareness about Lp(a) is personal.
When she was 22, her father died of a heart attack at age 50. She never thought the same thing would happen to her, given her own healthy lifestyle, but she didn’t realize she possessed a “hidden risk.”
She herself had been living, unaware, with Lp(a), resulting in a widow-maker blockage in an artery of her heart, which put her at the risk of dying of a severe heart attack by 39, she wrote.
“The myth has to be busted, people need to understand you can inherit risk factors for clogged arteries, you don’t have to have a bad lifestyle to end up having a heart attack, some people are born genetically predisposed to having cardiovascular disease,” she stressed.
How to find out if you have this form of cholesterol
The go-to cholesterol and lipid panel tests don’t include an Lp(a) blood test. You have to ask your doctor for a separate exam.
The U.S. National Library of Medicine recommends people who have heart disease (despite having normal results from other lipid tests), people with high cholesterol (even if they have a healthy diet), and those with a family history of heart disease (especially if it occurred at an early age or resulted in sudden death) should seek out the blood test.
Tremulis says that awareness is growing, and work is being done to develop effective treatments at managing Lp(a) levels.
The Centers for Disease Control and Prevention approved two ICD-10 codes for the diagnosis of elevated Lp(a) levels. This is the system healthcare providers use to classify and code symptoms and diagnoses in accordance with proper hospital care in the United States.
The new codes can help diagnose the condition in people who don’t show any symptoms, like Tremulis, who has both elevated Lp(a) levels and a family history of Lp(a) and high cholesterol. These guidelines will go into effect this October.
“These new diagnostic codes will enable clinicians to identify clearly in the medical record the presence of a strong risk factor for cardiovascular disease and to tailor prevention and treatment strategies,” she added.
While not widely discussed, Lp(a) is a common issue. The Lipoprotein(a) Foundation reports almost 63 million people in the United States have high Lp(a) levels. Given that it’s so common, why don’t we hear more about it?
Dr. Luke Laffin, a cardiologist at the Cleveland Clinic, told Healthline it’s simply because it’s not routinely screened.
“Lp(a) is not discussed as much because we do not screen most people for elevated levels of Lp(a), unlike LDL cholesterol. In fact, screening the population at-large is not recommended by most society guidelines around the world,” he said.
There are three main reasons for that.
“The first is that it is a genetically determined marker of cardiovascular risk that cannot be significantly modified with lifestyle changes,” Laffin said. “The second is that we do not have easily accessible or tolerable therapies to lower Lp(a) levels. The third reason is that medications that lower Lp(a) levels also lower LDL levels, so it has proven difficult to attribute clinically important effects — like a reduction in heart disease and strokes — to Lp(a) lowering alone.”
Given that the presence of Lp(a) is really driven by your genetics, Laffin says it’s difficult to lower your level even if you make significant lifestyle changes. He notes there are two main classes of medications approved for use in the United States, but they aren’t formally approved to treat elevated Lp(a) specifically.
These medications are nicotinic acid (niacin) and PCSK9 inhibitors. Right now, there are clinical trials to test new treatments, like antisense therapy to potentially reduce the body’s production of Lp(a), but “it is unknown whether this will actually provide cardiovascular benefits and the results are years away,” Laffin explained.
Who’s at risk?
Laffin says people with a strong family history of premature heart disease and heart events — men before the age of 55 and women before 65 — should be screened for Lp(a). He adds that people who are at an “intermediate” or “moderate” risk of a heart attack or stroke should also be tested.
“Elevated, or not elevated, Lp(a) levels help better risk stratify an individual patient and again inform discussions about starting or stopping cholesterol-modifying medications,” he said. “Finally, if a person has a personal history of early heart disease without other clear causative factors, we will typically screen for elevated levels of Lp(a).”
If you’re newly diagnosed and are unsure of what to do moving forward, Laffin suggests you shouldn’t discount lifestyle improvements, such as eating healthier and exercise. These still help manage your overall risk of cardiovascular disease.
“The basics are still very important, and include not smoking, maintaining a healthy weight, a diet of moderation, like fruits and vegetables, and regular exercise. I also would encourage you to seek the opinion of your regular physician or a cardiologist about more aggressive modification and treatment of risk factors, such as elevated LDL cholesterol and hypertension,” Laffin said.
“Ask his or her opinion about targeting even lower LDL cholesterol levels than they normally would in a person with your similar traditional risk factor profile, but without elevated Lp(a),” he adds.
Tremulis emphasizes she feels it’s important “that everyone be tested for high Lp(a) at least once in their lifetime so that this potential genetic risk factor for heart disease can be identified early.”
She says that beyond this, it’s necessary that people who have this kind of cholesterol should educate themselves by working with their doctors to come up with a heart disease prevention plan and stay vigilant about possible stroke or heart attack symptoms.