How this instrument works
A coronary artery calcium (CAC) score, also called an Agatston score, comes from a non-contrast CT scan of the heart. It quantifies how much calcified plaque has built up inside the coronary arteries — the higher the score, the more calcified atherosclerotic plaque is present. A score of 0 means no detectable coronary calcification on the scan.
'Arterial age' translates that raw score into a more intuitive number: the age at which an average person's coronary calcium burden would typically look like yours. The formula used here — 39.1 + 7.25 × log10(CAC score + 1) — comes from the Multi-Ethnic Study of Atherosclerosis (MESA), an NHLBI-funded, population-based cohort study (McClelland et al., 2009).
This calculator can only work from an actual CAC score obtained by a heart CT calcium scan — it isn't something that can be approximated from blood pressure, cholesterol, family history, or other standard risk factors. Two people with identical conventional risk-factor profiles can have very different measured calcium burdens, which is the reason the scan exists as a separate test in the first place.
- Enter the coronary artery calcium (Agatston) score from your heart CT calcium scan report.
- Read the resulting arterial age in years — the age at which an average person's coronary calcium burden would match the entered score.
Worked example — three CAC scores
A CAC score of 0 — no detectable coronary calcification — gives the formula's floor value: an arterial age of 39.1 years, regardless of the person's actual age.
A CAC score of 100 computes to 39.1 + 7.25 × log10(101) ≈ 53.6 years. Someone whose actual age is well under that number has coronary calcification more typical of an older person.
A CAC score of 400 computes to 39.1 + 7.25 × log10(401) ≈ 58.0 years.
Questions
What is a coronary artery calcium (CAC) score?
It's a measurement, also called an Agatston score, taken from a non-contrast CT scan of the heart. It quantifies calcified plaque within the coronary arteries — a score of 0 means none is detectable, and the score rises with the amount of calcified atherosclerotic plaque present. It's obtained through imaging, not a blood test or physical exam.
Where does the arterial age formula come from?
From McClelland RL, Nasir K, Budoff M, Blumenthal RS, and Kronmal RA, 'Arterial age as a function of coronary artery calcium (from the Multi-Ethnic Study of Atherosclerosis [MESA]),' American Journal of Cardiology, 2009;103(1):59-63. MESA is a large, NHLBI-funded, population-based cohort study of subclinical cardiovascular disease.
Can I calculate my arterial age without having had a calcium scan?
No. The formula requires an actual measured CAC score as input. It cannot be derived from blood pressure, cholesterol, blood glucose, family history, or any combination of standard risk factors — the whole premise of the CAC scan is that it captures anatomic plaque burden that isn't fully predictable from those factors alone.
Why does the formula give 39.1 years even at a CAC score of 0?
Mathematically, log10(0+1) = log10(1) = 0, so the formula reduces to its constant term, 39.1, whenever the score is 0. That's a property of the regression model MESA researchers fit to their cohort's data, not a claim that everyone with a zero score is at least 39 — it's simply the floor value the equation produces.
Is a higher arterial age than my actual age dangerous?
A higher arterial age reflects a greater burden of calcified coronary plaque than typical for your actual age, which the MESA researchers found was associated with elevated coronary risk in their cohort. It's one data point to discuss with a physician or cardiologist alongside your full risk profile — not a diagnosis or a standalone risk score.
Does this replace a cardiologist's cardiovascular risk assessment?
No. Arterial age is a way of presenting a single measurement (the CAC score) more intuitively; it doesn't incorporate blood pressure, lipids, diabetes status, smoking history, or family history the way a full risk calculator (such as the pooled cohort equations) does. Use it alongside, not instead of, a clinician's complete assessment.
References
- McClelland RL, Nasir K, Budoff M, Blumenthal RS, Kronmal RA — Arterial age as a function of coronary artery calcium (from MESA). Am J Cardiol. 2009;103(1):59-63 (PMID 19101230)
- MESA (Multi-Ethnic Study of Atherosclerosis) — Arterial Age Calculator, NHLBI-funded research cohort
Read this first: This instrument computes a screening figure from population formulas — it is not a diagnosis, and it cannot see the whole picture a clinician can. Use it to inform a conversation, not to replace one.