From the Guidelines
A high calcium score at the 50th percentile is not considered high and is actually average or normal for that age and sex group. The significance of a high calcium score is typically defined by values that exceed the 75th percentile for a person's age and sex, or when the absolute score is above 300 Agatston units 1. A score at the 50th percentile would be considered average or normal for that age and sex group. Calcium scores measure calcified plaque in coronary arteries, with higher scores indicating greater atherosclerosis and cardiovascular risk.
Key Points to Consider
- A score of zero indicates no detectable calcium, 1-99 is mild, 100-299 is moderate, and scores above 300 suggest extensive coronary artery disease 1.
- The presence of any measurable coronary calcium is independently related to hard and soft events in men and women at low to intermediate pretest risk, providing incremental prognostic information over conventional risk factors 1.
- Studies such as the MESA and the Heinz Nixdorf Recall study have demonstrated the prognostic use of a CAC score, with a net reclassification index of 25% and 24% respectively, indicating that CAC scores can aid in improved risk stratification beyond conventional risk factor–based scores alone 1.
Clinical Implications
- A positive calcium score can restratify asymptomatic patients with a family history of premature CAD to a high-risk category and can even reclassify those individuals without risk factors as higher risk than those with multiple risk factors but no coronary artery calcification 1.
- The AHA/ACC/AACVPR/AAPA/ABC/ACPM/ADA/AGS/APhA/ASPC/NLA/PCNA guideline suggests that patients with a 10-year risk of 5% to 7.5% may benefit from a CAC score prior to initiating statin therapy, especially in the presence of risk-enhancing factors 1.
Recommendations for Patients with a Calcium Score at the 50th Percentile
- Patients with a calcium score at the 50th percentile should discuss their results with their healthcare provider to interpret the score in the context of their overall cardiovascular risk profile and recommend appropriate preventive measures.
- Patients should be aware that a score at the 50th percentile is considered average or normal for their age and sex group, but it is still important to maintain a healthy lifestyle and follow preventive measures to reduce cardiovascular risk.
From the Research
Significance of a High Calcium Score at the 50th Percentile
- A high calcium score at the 50th percentile indicates a higher risk of coronary artery disease (CAD) and cardiovascular events 2, 3, 4.
- Studies have shown that individuals with coronary artery calcium scores above the 50th percentile have a higher risk of cardiovascular and all-cause mortality 3, 5.
- The 50th percentile score can be used as a threshold to identify individuals at higher risk of CAD, and can be used to guide treatment decisions 2, 6.
- Age- and sex-based nomograms can be used to determine the 50th percentile score for an individual, taking into account their age and sex 4, 6.
- A study of runners found that those who participated in extreme distance running had a higher rate of coronary artery calcification, and were more likely to have calcium scores above the 50th percentile 5.
Risk Stratification
- Coronary artery calcium scores and percentiles can be used to stratify individuals into different risk categories 2, 3, 6.
- Individuals with calcium scores above the 50th percentile may be considered at higher risk of CAD and cardiovascular events, and may require more aggressive treatment and lifestyle modifications 3, 5.
- The use of age- and sex-based nomograms can help to identify individuals at higher risk, and can be used to guide treatment decisions 2, 4, 6.
Clinical Implications
- The significance of a high calcium score at the 50th percentile should be considered in the context of an individual's overall cardiovascular risk profile 2, 3, 6.
- Clinicians should use age- and sex-based nomograms to determine the 50th percentile score for an individual, and should consider this information when making treatment decisions 4, 6.
- Further research is needed to fully understand the clinical implications of a high calcium score at the 50th percentile, and to develop more effective strategies for preventing and treating CAD 2, 3, 5.