New cholesterol guidelines advise doctors to begin screening and treating people in their 30s, long before the risks of a heart attack and stroke become significantly higher.
For the first time, the American Heart Association, along with the American College of Cardiology and other medical groups also recommend screening for two biomarkers in the blood that have been linked to heart risks.
The updated guidance was jointly published Friday in Circulation and the Journal of the American College of Cardiology.
The guidelines — the first revamp since 2018 — focus on controlling dyslipidemia, or abnormal levels of blood lipids such as cholesterol and triglycerides.
One in 4 U.S. adults have high LDL, or “bad,” cholesterol, a form of dyslipidemia and risk factor for heart attack and stroke, according to estimates from the heart association.
“We’re trying to help clinicians and patients decide: When should medicine be considered?” said Dr. Roger Blumenthal, the chair of the guideline writing committee and director of the Johns Hopkins Ciccarone Center for the Prevention of Cardiovascular Disease in Baltimore. “We always want to try to strive to improve lifestyle habits at each and every visit but sometimes medication can be very helpful if lifestyle doesn’t do the trick.”
Dr. Christopher Kramer, a cardiologist at the UVA Health Heart and Vascular Center in Charlottesville, Virginia, said the most important takeaway from the new guidelines is that heart disease prevention must begin earlier. Kramer is also the president of the American College of Cardiology but wasn’t part of the guideline writing committee.
“We’re changing the way we measure risk,” he said. “Not just assessing 10-year risk but also assessing 30-year risk, and that goes back to it being a lifelong disease.”
Lowering lifetime LDL cholesterol
For patients in their 30s, doctors are now encouraged to use a newer calculator, PREVENT, to determine the risk for developing atherosclerotic cardiovascular disease, a type of heart disease caused by plaque buildup in the arteries.
The PREVENT tool, which takes into account factors such as body mass index, cholesterol levels and tobacco use, calculates the 10-year risk for people 30 to 79 and 30-year risk for people 30 to 59. The updated 10-year risk categories are:
- Low: less than 3%
- Borderline: 3% to less than 5%
- Intermediate: 5% to less than 10%
- High: 10% or higher.
Blumenthal said the new guidelines will be especially important for people who smoke tobacco, have high blood pressure, high blood sugar, Type 2 diabetes or a family history of heart disease.
“It gives them some context about the importance of whether or not they need to be more aggressive earlier with lifestyle changes,” he said.
The guidelines recommend statins, a type of medication designed to lower cholesterol, for adults 30 and older with LDL cholesterol levels of 160 milligrams per deciliter of blood or higher.
Dr. Steven Nissen, the chief academic officer of the Cleveland Clinic Sydell and Arnold Miller Family Heart, Vascular and Thoracic Institute, said early intervention is intended to limit long-term exposure to LDL cholesterol.
“The time-averaged value of your LDL cholesterol over your lifetime is one of the strongest predictors of whether you’re going to have a heart-related event,” said Nissen, who wasn’t part of the guideline writing committee. “It’s really about reducing lifelong risk, not 10-year risk.”
In his view, previous iterations of the guidelines were too conservative. He’s more satisfied with the new recommendations, which advise doctors to consider LDL-lowering treatment for patients with borderline or intermediate 10-year risks of heart disease.
“This is much lower than ever before,” Nissen said. “What they’re basically saying is, don’t rule out treating somebody who’s only got a 3% 10-year risk if their lifetime risk is high.”
Clear LDL targets
Dr. Karol Watson, the director of the UCLA Health Women’s Cardiovascular Center, co-authored a commentary published in Circulation alongside the new guidelines, which she called an extension of the previous version.
“This is not a sea change; we are still managing lipids to reduce atherosclerotic events,” she said. “As a preventive cardiologist, I can tell you that’s the best strategy we’ve had yet to prevent heart attacks, strokes and cardiovascular death.”
The new guidelines provide “a more precise, individualized, and equitable approach” to heart disease prevention, Watson wrote in the commentary.
The guidelines bring back clear targets for LDL cholesterol. For most people without risk factors, doctors now aim for LDL levels below 100 mg/dL, or milligrams per deciliter of blood.
For people at higher risk, the goal drops below 70 mg/dL. For patients who already have heart disease, the target gets even lower, below 55 mg/dL.
Research shows that people with heart disease have fewer heart attacks and strokes when they are treated to a target LDL below 55 mg/dL.
However, individual cholesterol tolerance may vary, Watson said, citing an active, 70-year-old patient of hers who had always had low cholesterol but still experienced a ministroke.
“Everybody knows someone whose cholesterol was super, super high and they lived to be 90,” she said. “Each individual has their own level at which their arteries are permissive to let cholesterol in.”
Adds ApoB testing
The new guidelines also suggest testing for apolipoprotein B (apoB), a protein that attaches to harmful fat particles in the blood. The apoB protein is found on the surface of harmful lipoproteins like LDL that contribute to heart disease.
Previous guidelines didn’t recommend routine testing for apoB as part of cholesterol screening, except for some patients with high triglycerides.
“That could be yet another target of further lipid lowering, because lowering apoB is associated with reduced risk,” Kramer said.
In particular, apoB testing may paint a clearer picture of risk for people with high triglycerides, Type 2 diabetes or cardiovascular-kidney-metabolic syndrome.
Everyone needs Lp(a) testing — once
Also new this year is the recommendation that everyone get lipoprotein(a) testing at least once in adulthood. Lp(a) is a type of cholesterol that is undetected by routine tests. It’s determined by genetics and minimally affected by changes in diet or exercise. People with high levels of Lp(a), an estimated 64 million adults in the U.S., are at extremely high risk of cholesterol buildup in their arteries.
“It should be considered as a risk-enhancing factor,” Nissen said. “If your levels are elevated, it means that you may want to treat more intensively, even if the LDL isn’t quite as high as you might otherwise expect.”
Lp(a) is measured in nanomoles per liter. A level greater than 250 nmnol/L roughly equates to a two-fold increase in heart disease risk, while a level above 430 nmol/L indicates a four-fold risk.
“There are no currently available treatments for lowering Lp(a), so a lot of people are like, ‘Well, why am I testing it?’” Watson said. “Most of the reason is to get a better overall assessment of risk.”
The new guidelines also recommend screening for calcium buildup in the coronary arteries for men ages 40 and older and women 45 and older who have a borderline or intermediate 10-year risk of heart attack or stroke.
Regardless of the change in screening guidelines, the risk factors for heart disease remain the same.
“It’s cholesterol, blood pressure, diabetes, smoking, obesity,” Kramer said. “People need to concentrate on lowering their risk factors and let their physicians worry about calculating the numbers and deciding on whether or not they need cholesterol lowering.”
Heart disease is the leading cause of deaths worldwide. In the U.S., it kills every 34 seconds, according to the heart association. Yet, the organization also estimates that as much as 80% of heart disease and strokes are preventable with lifestyle changes.
“If you wait until people get to 55 or 60, a lot of the damage has already been done,” Nissen said. “They’ve got plaques in the coronaries, and it’s hard to undo the problem.