What Is a Good Calcium Score for a 65-Year-Old?

A calcium score of zero is the best result at any age, including 65. Zero means no detectable calcified plaque in the coronary arteries and places you in a low-risk category for heart attack and cardiovascular death over the next several years. But because coronary calcium accumulates with age, a score of zero becomes less common in your mid-sixties, and a low but non-zero score does not automatically spell trouble. What matters is where your number falls relative to others your age and sex, and how that number interacts with your other risk factors.

How a Calcium Score Works

A coronary artery calcium (CAC) scan is a quick, non-contrast CT of the chest that detects and measures calcium deposits embedded in the walls of the arteries feeding your heart. The scan takes only seconds and uses a low dose of radiation, typically around 1 millisievert on modern scanners, which is roughly what you’d absorb from natural background radiation over three to four months.¹ The scoring method in near-universal use was introduced by Dr. Arthur Agatston in 1990, and every score you see reported in clinical practice refers to this Agatston score.² The number itself reflects both the area and the density of calcium deposits across all three major coronary arteries.

The calcium being measured is not a fluke finding. It forms through a process in which cells in the artery wall begin to behave like bone-forming cells, laying down mineral in and around fatty plaques.³ A higher score indicates a larger total burden of calcified plaque. That said, the relationship between your number and your actual risk is not perfectly linear, and the score’s meaning shifts depending on your age, sex, and ethnic background.

Score Categories and What They Mean

Clinicians generally group Agatston scores into a few broad categories. These thresholds were not derived from a single biological breakpoint; they emerged from decades of outcomes data and are, as one review put it, somewhat arbitrary in origin, though they have proven consistently predictive of events.⁴

• Zero: No detectable calcified plaque. Low risk. This is the best possible result.
• 1 to 99: Mild calcification. Plaque is present but the absolute burden is small.
• 100 to 399: Moderate calcification. Risk is clearly elevated compared with zero, and treatment decisions often pivot on this range.
• 400 and above: Extensive calcification. High risk for cardiovascular events.
• 1,000 and above: Very high. Researchers now treat this as a distinct category carrying the most serious prognosis.

For someone at 65, having a score in the 1–99 range is common and does not mean a heart attack is imminent. A score in the 100–399 range deserves closer attention. A score above 400, and especially above 1,000, puts you in a group where aggressive prevention is strongly warranted.

Why Percentiles Matter More Than Raw Numbers at 65

Raw Agatston scores climb with age in almost everyone, even people who eat well and exercise. A score of 150 in a 45-year-old man is far more alarming than 150 in a 70-year-old man, because it places the younger person much higher on the distribution curve for his age group. Large pooled analyses have established age-and-sex-specific percentile tables so that clinicians can compare your score against what is typical for someone like you.⁵ At age 65, a woman will generally have lower average calcium scores than a man of the same age because women develop coronary calcification roughly a decade later. Being above the 75th percentile for your age and sex signals higher relative risk even if your absolute number looks “moderate.”

So when you ask what is “good,” the honest answer is: zero is good, a low percentile rank is reassuring, and anything above the 75th percentile for your demographic warrants a conversation about treatment regardless of the raw number. Your doctor can look up the exact percentile using publicly available tables derived from the Multi-Ethnic Study of Atherosclerosis (MESA) and similar cohorts.

The Power of a Zero Score

A zero score is not just “low risk”; it functions as a strong signal that you can safely defer aggressive preventive treatment for a while. The literature consistently shows that a CAC of zero acts as a powerful downward risk reclassifier, even in older adults whose age alone might suggest higher risk.⁶ In the MESA cohort, a zero score was also associated with low risk of non-cardiovascular death, reinforcing that it reflects broader biological health rather than just cardiac health.⁷

That said, a zero score does not guarantee zero risk. In one large study of symptomatic patients, about a third of first heart attacks or deaths during follow-up occurred in people who had a CAC of zero.⁸ This is partly because calcium scoring only detects calcified plaque. Soft, non-calcified plaque, which can also narrow arteries and rupture, is invisible on a standard calcium scan.

What a Calcium Score Cannot See

One of the most important limitations of this test is that it misses non-calcified (“soft”) plaque entirely. A meta-analysis pooling data from over 37,000 patients with a zero calcium score found that roughly 10% still had some non-calcified plaque visible on CT angiography, and about 1% had obstructive non-calcified plaque.⁹ Among smaller studies, one found that about 9% of patients with a zero calcium score had some atherosclerotic plaque, and nearly half of those individuals had significant blockages.¹⁰

The practical takeaway is that a zero calcium score is a reassuring finding but not a license to ignore symptoms. If you have chest pain, shortness of breath, or other warning signs, a zero CAC score does not rule out coronary artery disease. Risk factors like diabetes and hypertension are particularly worth noting here: the meta-analysis found that both were significantly associated with having non-calcified plaque despite a zero calcium score, and male sex was the strongest predictor.⁹

Scores Above 400 and the 1,000-Plus Category

A score of 400 or higher signals extensive coronary calcification and is generally considered the threshold for high risk. But research from the MESA cohort has shown that people scoring 1,000 or higher deserve to be treated as a separate category altogether. Compared with a score of zero, a CAC of 1,000 or above carried roughly a five-fold increased risk of any cardiovascular event, a nearly eight-fold increased risk of coronary events, and about a two-fold increase in death from any cause. Even compared with the already-high-risk 400–999 group, 1,000-plus carried meaningfully higher hazards for heart attacks, cardiovascular death, and even non-cardiovascular events.¹¹ No upper ceiling was found: the higher the score, the worse the outcomes, with no point at which additional calcium stopped mattering.

For a 65-year-old, landing in the 1,000-plus zone usually means decades of plaque accumulation and a need for aggressive medical management, including high-intensity statin therapy and tight blood-pressure control. The annualized rate of major adverse cardiovascular events at this level was about 3.4 per 100 person-years, similar to what is seen in secondary prevention trials among patients who have already had a heart attack or stroke.¹¹

How a Calcium Score Shapes Treatment Decisions

Both the American College of Cardiology/American Heart Association and European guidelines recommend CAC scoring as a tool for refining risk in people who fall in the gray zone for preventive treatment, particularly decisions about starting a statin. For people whose estimated 10-year cardiovascular risk is intermediate, the calcium score can push you clearly into a treatment group or reassure you that medication can wait.¹²

A zero score is particularly useful here. Even in people with risk-enhancing factors like chronic kidney disease or elevated inflammatory markers, a CAC of zero was associated with event rates below the threshold where statin therapy is typically recommended, with a single exception: those with a very low ankle-brachial index, a marker of peripheral artery disease.¹³ In other words, a zero score can allow you to defer statin therapy even if other factors suggest you might need it.

Aspirin decisions are similarly informed by calcium scoring. In people under 70 without high bleeding risk, a CAC of 100 or more identified a group where aspirin’s benefit in preventing cardiovascular events outweighed its bleeding risk. When the calcium score was zero, however, aspirin’s harm from bleeding exceeded any cardiovascular benefit.¹⁴ The relationship between aspirin benefit and calcium score held across multiple studies, though one analysis struck a more cautious note: if bleeding risk is elevated, aspirin can be net harmful regardless of CAC value, and in people at very high estimated cardiovascular risk (above 20% over 10 years), aspirin showed potential benefit even in those with lower calcium scores.¹⁵

Not All Calcium Is Created Equal

The Agatston score bundles two things together: how much calcium there is (volume) and how dense that calcium is. Research has shown these components pull in opposite directions. Greater calcium volume is associated with higher risk of heart disease and death, as you would expect. But denser calcium, per unit of volume, is associated with lower risk. A large study in the MESA cohort was the first to split these apart, finding that each standard-deviation increase in calcium density was tied to a roughly 27–29% decrease in risk for coronary and cardiovascular events, even after accounting for volume.¹⁶ A later meta-analysis confirmed the pattern: higher calcium density was independently linked to about a 20% lower risk of cardiovascular events for every standard-deviation increase.¹⁷

The prevailing theory is that dense, heavily calcified plaque is more stable, less prone to rupturing and causing a heart attack, while lower-density or spotty calcium marks younger, more unstable plaque. Your standard report will not break the score down this way, but this research explains a puzzling clinical observation: some people with moderately elevated Agatston scores do surprisingly well, while others with similar scores do not. The distribution and density of the calcium matter, not just the total.

The Intermediate Range and Plaque Number

If your score falls between 100 and 399, you are in the zone where the calcium score by itself tells only part of the story. One large study found that in this intermediate range, the number of individual calcified plaques significantly improved prediction of death risk beyond what the Agatston score alone provided. Adding plaque count improved classification of who would die and who would not by about 29%.¹⁸ For scores under 100, having six or more plaques was also tied to higher mortality. Above 400, the risk was high regardless of plaque number.

This is worth knowing because it underscores that the single number on your report is a useful summary, but the underlying anatomy matters. If you are in the intermediate range and your doctor orders follow-up imaging, the specific layout of plaque across your coronary arteries helps refine how aggressively you should be treated.

How Long a Zero Score Lasts

If your CAC scan comes back zero, you probably do not need another one right away. Research on the “warranty period” of a zero score suggests it holds up for roughly four to five years before a meaningful number of people begin converting to positive scores. In one study, about 25% of initially zero-score patients developed detectable calcium over follow-up, with the average time to conversion around four years and the highest conversion rate in the fifth year.¹⁹ MESA data showed that the warranty period before a quarter of people would test positive ranged from three to seven years depending on sex and race, and progression to clinically significant levels (CAC above 100) within 10 years was rare.²⁰ For a 65-year-old with a zero score, repeating the scan in about five years is a reasonable interval unless new symptoms or risk factors develop.

Once you do have a positive score, the story changes. Progression of calcium over time predicts mortality in people who started with some calcium, though in those who started at zero, the small amount of progression typically seen did not itself predict death.²¹ There is no established guideline for repeat scanning intervals once calcium is present, and most insurers do not cover serial scans.

Racial and Ethnic Differences in Risk at the Same Score

Your calcium score does not carry the same prognosis for everyone. The MESA study demonstrated that the prevalence and quantity of coronary calcium differ across racial and ethnic groups even after adjusting for traditional risk factors like cholesterol, blood pressure, and smoking.²² White men tend to have the highest average calcium scores, while Black, Hispanic, and Asian individuals tend to have lower average scores at the same age.

But here is where it gets complicated: lower average calcium scores in Black adults do not translate to lower risk. Data from the CAC Consortium showed that Black women and men had the highest cardiovascular mortality at every calcium score level, including zero. Black men and women with a CAC of zero or a low estimated risk score still had hazard ratios six to nine times higher than other groups.²³ Hispanic participants fell in an intermediate range. These disparities likely reflect a combination of factors the calcium score does not capture: differences in non-calcified plaque burden, access to preventive care, and the cumulative effects of social and environmental determinants of health. The finding is a reminder that a calcium score must be interpreted in the context of the whole patient, not as a standalone verdict.

The Exercise Paradox

Highly active people sometimes discover, to their dismay, that years of endurance exercise have not protected them from coronary calcium. In fact, lifelong endurance athletes appear more likely to have coronary plaque than sedentary controls. One study found that long-term endurance sport participation was associated with roughly 1.6 to 2.8 times higher odds of having calcified, non-calcified, or mixed plaques compared with controls.²⁴

Before you cancel your gym membership: the type of plaque matters. Athletes’ plaques tend to be predominantly calcified rather than soft, and heavily calcified plaque is more stable and less likely to rupture.²⁵ This may explain why athletes with elevated calcium scores seem to have lower cardiovascular event rates than sedentary people with similar numbers. The calcium density research described earlier supports this interpretation: dense calcium is protective, and exercise may promote stable calcification rather than the dangerous, rupture-prone kind. If you are 65, fit, and shocked by a non-zero calcium score, the context of your activity history and plaque characteristics matters more than the headline number.

Cost and Insurance Coverage

One frustrating reality is that despite guideline endorsements from both American and European cardiology societies, most insurers still do not routinely cover CAC imaging for primary prevention. Patients are typically required to pay out of pocket, with costs ranging from about $75 to $400 depending on the facility. A recent analysis argued that this coverage gap leads to underdiagnosis and failure to prevent costly cardiovascular events down the line.²⁶ For a 65-year-old covered by Medicare, the scan is generally not covered as a screening test, though it may be reimbursed if ordered in a diagnostic context (for example, to evaluate chest pain). Some stand-alone imaging centers offer cash-pay pricing that undercuts hospital-based facilities. Given how effectively a calcium score refines treatment decisions at this age, the out-of-pocket cost is modest relative to the information gained.

Incidental Findings on the Scan

Because a CAC scan captures a slice of your chest, the images sometimes reveal findings unrelated to your coronary arteries. One study found clinically significant incidental findings in about a quarter of patients, including lung nodules, aortic abnormalities, and other abnormalities that might have been missed on a more narrowly focused scan.²⁷ This can be a double-edged sword: occasionally, an incidental finding leads to early detection of something serious like lung cancer. More often, it triggers a cascade of follow-up imaging and anxiety for findings that turn out to be benign. If you get a CAC scan, be aware that you may hear about things other than your calcium score, and not all of them will require treatment.