The Coronary Artery Calcium (CAC) score is a powerful tool in cardiovascular risk assessment, providing a direct measurement of subclinical heart disease. Receiving this number can be unsettling, especially for older adults. For a 70-year-old woman, interpreting this score requires moving beyond simple ranges and considering how age and biological sex influence what is considered a typical result. Understanding this context is the first step toward a personalized strategy for heart health management.
Understanding the Coronary Artery Calcium Score
The CAC score is derived from a specialized, non-invasive computed tomography (CT) scan, often referred to as a Heart Scan. This test specifically images the heart to detect calcium deposits within the walls of the coronary arteries. The presence of calcium in this location is virtually always a sign of atherosclerosis, or the buildup of plaque.
The resulting measurement, known as the Agatston score, quantifies the total area and density of these calcified plaques. A higher score indicates a greater burden of calcified plaque, which is strongly correlated with an increased future risk of a heart attack or other cardiac events.
Interpreting the Score Categories
The Agatston score uses numerical ranges to stratify an individual’s risk for atherosclerotic cardiovascular disease (ASCVD). A score of zero is the most favorable result, indicating no detectable calcium and correlating with a very low risk of a cardiac event over the next decade. This finding allows for a significant downgrading of overall cardiovascular risk.
Scores between 1 and 100 represent mild calcification, suggesting a low-to-moderate plaque burden and a relatively low risk. When the score falls between 101 and 400, it denotes moderate plaque accumulation and places the individual into an intermediate-to-high risk category. This range often serves as a tipping point for deciding on more aggressive preventive therapies.
A score exceeding 400 signifies an extensive plaque burden and is associated with a high future risk of a cardiac event. This numerical range suggests a high probability of significant coronary artery disease. These classifications are universal starting points, but their meaning changes depending on the age and sex of the person being tested.
Contextualizing Scores for a 70-Year-Old Woman
For a 70-year-old woman, the interpretation of the CAC score shifts significantly because some degree of calcification is an expected consequence of the aging process. A score that might be considered high-risk for a woman in her 50s may simply be an average result for a woman two decades older. Therefore, the score is best interpreted by using percentile rankings, which compare a woman’s result to others of the same age and sex.
A score is considered “normal” or average if it falls around the 50th percentile for her demographic. For a 70-year-old woman, the median score, or 50th percentile, is non-zero and often falls into the mild-to-moderate range of absolute scores. While data varies by study and ethnicity, a score in the low hundreds, such as between 100 and 200, is a common finding in this age group and may represent an average burden of plaque relative to her peers.
The most concerning scores are those that place a woman above the 75th percentile for her age. For women younger than 70, a score over 100 is often already above this elevated percentile threshold. For the 70-year-old woman, a score of 300 or more is typically a significant finding, placing her in the highest risk percentiles of her age group.
A score of 0, even at age 70, remains an extremely reassuring result, placing her in the lowest percentile and suggesting a very low likelihood of experiencing a cardiac event. The focus should be on the percentile rank, rather than the absolute number alone, to determine if the plaque burden is excessive compared to her peers.
Actionable Steps Following a CAC Result
Regardless of the score received, the next step is to review the results with a cardiologist or primary care physician who can integrate the finding with the full clinical picture. A CAC score is a single data point that must be combined with blood pressure, cholesterol levels, family history, and other risk factors. The score does not diagnose an active blockage but serves as a powerful guide for preventive treatment.
For a score of zero, the treatment plan centers on maintaining a heart-healthy lifestyle, which includes diet, exercise, and smoking cessation. This result can often lead to a decision to withhold cholesterol-lowering medications like statins, which is a major benefit of the test. A repeat scan may be considered in five to ten years to monitor for any new plaque development.
If the score falls into the mild-to-moderate range (1 to 400), the physician will likely recommend aggressive risk factor modification. This commonly involves initiating or intensifying statin therapy, especially if the score is above 100, or if the percentile ranking is high. The goal of medication is not to reduce the calcium, which is static, but to stabilize the underlying soft, non-calcified plaque and prevent future events.
A very high score (over 400) or a score in the highest percentile mandates aggressive pharmacological intervention, typically involving high-intensity statins and careful management of blood pressure and blood sugar. In these cases, a physician may also consider further testing, such as a stress test, to determine if there is any significant underlying blood flow restriction.