What is a coronary calcium screening and how can it assess cardiovascular risk in adults with intermediate risk factors such as family history of heart disease, high blood pressure, high cholesterol, smoking, or diabetes?

What is a Coronary Calcium Screening?

A coronary calcium scan is a quick, painless CT scan of your heart that measures calcium deposits in your coronary arteries—the blood vessels that supply your heart with oxygen-rich blood—and this calcium is a direct marker of atherosclerosis (plaque buildup) that helps predict your risk of having a heart attack or dying from heart disease in the next 5-10 years. 1, 2

How the Test Works

• The scan takes only a few minutes and requires no needles, dyes, or special preparation 1
• You lie on a table while a CT scanner takes pictures of your heart between heartbeats 1
• The radiation exposure is very low—equivalent to 1-2 mammograms (about 1.5 mSv) 1, 3
• The test produces a "calcium score" (also called an Agatston score) that quantifies the amount of calcified plaque in your coronary arteries 1, 4

Why This Test Matters for You

The calcium score is one of the most powerful predictors of future heart attacks and cardiac death, often providing more information than traditional risk factors like cholesterol, blood pressure, and family history alone. 1, 5, 6

Understanding Your Score

• Score of 0: You have an extremely low risk of a heart attack in the next 5-10 years (less than 1% at 10 years), and you likely don't need aggressive preventive medications like statins 2, 4, 7

• Score of 1-100: Low risk (less than 10% at 10 years), though if you're 55 or older, statin therapy may be reasonable 2, 3, 4

• Score of 100-400: Intermediate to moderately high risk (10-20% at 10 years), especially if your score is above the 75th percentile for your age and sex—statin therapy is recommended 2, 3, 4

• Score above 400: High risk (greater than 20% at 10 years)—you need aggressive treatment with lifestyle changes and medications 2, 4, 7

Who Should Get This Test?

This test is most valuable for people at intermediate risk—those with a 7.5-20% chance of having a heart attack in the next 10 years—where the results will actually change treatment decisions. 2, 3

You're a Good Candidate If You Have:

• Family history of early heart disease (parent or sibling with heart attack before age 55 in men, 65 in women) 1, 2, 3
• High cholesterol or high blood pressure that's borderline for medication 2, 3
• Diabetes 1, 3
• Current or past smoking 1
• Metabolic syndrome or chronic kidney disease 3
• Uncertainty about whether to start a statin medication 2, 3

You Should NOT Get This Test If:

• You're already at high risk and clearly need aggressive treatment (the test won't change your management) 3, 4
• You're at very low risk with no risk factors (the test is unlikely to show anything and won't change your care) 1, 3, 4
• You're a man under 40 or a woman under 50 (calcium is rarely present at these ages) 1, 3
• You already have known heart disease or symptoms like chest pain (you need different testing) 2, 3

The Real-World Impact

Studies following tens of thousands of people show that those with calcium scores above 100 have 4-10 times higher risk of heart attack and death compared to those with zero calcium. 1

• In one study of over 27,000 people, those with a score of 0 had only a 0.4% event rate over 3-5 years, while those with scores above 1000 had a 7.1% event rate 1
• Among younger adults (ages 30-49) with risk factors, having any calcium present increased the risk of heart disease death by 10-fold 1
• Even in low-risk patients with family history, a calcium score above 100 showed 10.4 times higher risk of coronary heart disease 1

How This Changes Your Treatment

The calcium score helps you and your doctor make smarter decisions about preventive medications, particularly statins, by identifying who will benefit most and who can safely avoid unnecessary treatment. 1, 2, 3

• If your score is 0, you can often avoid or delay statin therapy and recheck in 5-10 years 2, 3, 4
• If your score is elevated (≥100 or ≥75th percentile), the benefits of statin therapy clearly outweigh any risks 1, 2, 3
• Studies show that knowing your calcium score motivates patients to take their medications and make lifestyle changes—in one study, medication use increased from 44% to 90% in those with high scores 1

Practical Considerations

• The test typically costs less than $100 out-of-pocket at many centers 2, 3
• Insurance coverage varies but generally covers intermediate-risk patients where treatment decisions are uncertain 3
• The test should only be done if the results will actually change your treatment plan 3, 4
• A repeat scan is generally not needed for at least 5 years if your initial score is 0 4

Important Caveats

• A score of 0 does NOT mean you have no plaque—it only means you have no calcified plaque 3. Soft, non-calcified plaque can still be present but is rare in truly asymptomatic people
• The test detects calcium in coronary arteries specifically, not other types of heart problems like valve disease or heart muscle problems 1
• Incidental findings (like lung nodules) are found in up to 16.5% of scans and may require follow-up 1
• Women tend to have lower scores than men at the same age, so age/sex-specific percentiles matter 1