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A new study found that CT scans do a better job than genetic testing at determining heart disease risk when conventional factors are also taken into account. Reza Estakhrian/Getty Images
  • Conventional factors for assessing a person’s heart disease risk are helpful but may not always be the most accurate risk indicators on their own.
  • To improve risk assessments, medical professionals may use genetic testing and CT scans.
  • A new study compared genetic testing to CT scans and found that CT scans do a better job at determining heart disease risk for middle-aged adults when conventional factors are also taken into account.

Doctors use different factors to estimate a person’s risk for heart attack, stroke, or other cardiovascular problems. This estimate takes into account conventional risk factors such as age, sex, cholesterol levels, blood pressure, diabetic status, and smoking status, among others.

When combined, this information helps doctors decide when to recommend lifestyle changes, lipid-lowering statins, or other medications. Early treatment of underlying factors can reduce the risk of having a cardiovascular problem.

While these conventional factors may provide a good assessment of a person’s risk, there is room for improvement. For example, some people may experience a heart attack or other cardiovascular issues even when these factors do not indicate they are at high risk.

To improve risk assessment, scientists have suggested including other methods. One of these is a polygenic risk score, which is based on more than 6 million commonly occurring genetic variants associated with heart disease.

Another method is a CT scan for coronary artery calcium, which is a sign of atherosclerosis, a thickening or hardening of the arteries.

Now, in a new study, published May 23 in JAMA, researchers found that CT scans for coronary artery calcium do a better job than genetic testing at estimating a person’s risk of heart disease during mid-life, when added to conventional factors.

“These findings support recommendations to consider CT screening to calculate risk for heart disease in middle-aged patients when their degree of risk is uncertain or in the intermediate range,” Dr. Sadiya Khan, a cardiologist and assistant professor of medicine and preventive medicine at Northwestern University Feinberg School of Medicine, said in a news release.

The American College of Cardiology’s ASCVD Risk Estimator measures the risk for atherosclerotic cardiovascular disease. Low risk means someone has less than a 5% chance of developing cardiovascular disease due to atherosclerosis in the next 10 years. Above a 7.5% intermediate risk, statins are recommended.

For the study, researchers looked at data from over 3,200 middle-aged and older adults ranging from 45 to 79 years old from two groups, one in the United States and the other in the Netherlands. All participants were of European descent, so the results may not apply to other groups.

The researchers assessed participants’ risk of coronary heart disease using conventional risk factors.

The participants also had a CT scan done to determine their coronary artery calcium score and a genetic test to estimate their polygenic risk score.

Researchers followed people for up to 17 years, with regular in-person exams and telephone check-ins.

Based on conventional factors, participants’ risk of cardiovascular disease was 6% to 7% on average, researchers found. In contrast, around 8% to 9% of people developed heart disease during the follow-up period.

When researchers considered the coronary artery calcium score alongside conventional factors, however, the risk estimate became greater. In contrast, the genetic score had no impact.

“This suggests that incorporating genetic information through polygenic risk scores … may have limited clinical utility in predicting coronary heart disease risk, compared to traditional risk factors and the coronary artery calcium score,” Dr. Elliott J Elias, a cardiologist at Baptist Health Miami Cardiac & Vascular Institute, told Healthline.

Elias, who was not involved in the new study, pointed out that more research is needed to determine how well coronary artery calcium scores predict longer-term outcomes, as well as the cost-effectiveness and feasibility of this test in different healthcare settings.

The authors of the new study write that more research is also needed to show whether improving heart disease risk assessments translate to better outcomes for individuals.

For example, when doctors communicate this greater risk to their patients, are they more likely to take steps to lower that risk, such as by changing their diet or taking statins or blood pressure medication?

A 2022 study by Australian researchers sought to answer this question.

While the results of the study found that coronary artery calcium score is useful for predicting heart disease risk, the authors said there may still be a use for genetic scores.

“It is possible that the polygenic risk score and coronary artery calcium score may each be clinically relevant at different life stages,” they wrote.

Participants in the study were middle-aged or older, so they were more likely to have some amount of calcium in the arteries around the heart, which represents early signs of heart disease.

Younger adults, though, may not have developed coronary artery calcium, the researchers said. In this case, a genetic score may be able to identify people who have a higher genetic risk of developing heart disease later on.

Dr. Mary Greene, a cardiologist with Manhattan Cardiology in New York City, said a coronary artery calcium score test is already recommended for people with a borderline to intermediate risk of coronary artery disease. This test helps refine the risk assessment.

This recommendation is included in the 2019 American College of Cardiology and American Heart Association guidelines on the prevention of cardiovascular disease.

“All persons over 40 years old with at least one cardiovascular risk factor should be getting a coronary artery calcium score,” Green told Healthline.

Risk factors may include:

  • family history of coronary artery disease
  • heart attack
  • sudden cardiac death
  • personal history of high blood pressure
  • high cholesterol
  • type 2 diabetes
  • peripheral artery disease
  • stroke

Green added that obtaining coronary artery calcium scores in lower risk groups who may have previously been overlooked will provide the “opportunity to aggressively modify their risk factors before overt clinical symptoms of heart disease occur.”

“Additionally, going to the cardiologist to be risk-stratified for heart disease can enable one to identify all possible risk factors and manage those risk factors before the overt clinical disease is diagnosed,” she said.

People who are at higher risk of heart disease — including those who have a higher genetic risk — can take steps to lower that risk.

“Taking proactive steps such as quitting smoking, adopting a healthy diet, engaging in regular physical activity, and maintaining a healthy weight are crucial for lowering the risk of heart disease,” Elias said.

If your doctor diagnoses you with a health condition such as high blood pressure, type 2 diabetes and high cholesterol, managing these with lifestyle changes and medications can help lower the risk of heart disease.

Elias emphasized that reducing your risk of heart disease is not something you do alone but in partnership with your healthcare team.

“Encouraging patients to actively participate in their own care by implementing lifestyle modifications and adhering to prescribed treatments is essential for enhancing overall cardiovascular health,” he said.

Medical professionals assess people for heart disease by taking conventional factors like age, sex, and blood pressure levels into account.

While these conventional factors are useful, they are not the only factors for determining heart disease risk. Other methods like genetic testing and CT scans may help provide a more thorough picture of a person’s cardiovascular health.

A new study compared the use of CT scans and genetic testing alongside conventional factors and found that CT scans were more effective at determining heart disease risk, but genetic scores may still be useful.

Healthy lifestyle choices, weight management, regular physical activity, and avoiding smoking may help reduce your risk of developing cardiovascular problems.