At what age should calcium scoring for cardiovascular disease risk assessment be started?

Coronary Artery Calcium Scoring: When to Start

Coronary artery calcium (CAC) scoring should be initiated at age 40 for asymptomatic adults with intermediate cardiovascular risk, with selective use in younger individuals who have significant risk factors. 1, 2

Age-Based Recommendations

• Primary recommendation: Ages 40-75 years

  • Focus on individuals with intermediate risk (5-20% 10-year ASCVD risk)
  • Particularly valuable for those with borderline to intermediate risk (5-19.9% 10-year ASCVD risk) 1

• Selective use before age 40:

  • Type 1 diabetes <35 years with diabetes duration <10 years
  • Type 2 diabetes <50 years with diabetes duration <10 years
  • Strong family history of premature ASCVD 1

Risk-Based Stratification for CAC Testing

1. Low risk (<5% 10-year ASCVD risk):

   • Generally not recommended unless there's a strong family history of premature CAD
   • CAC testing may be reasonable for selective patients with family history of premature ASCVD 1

2. Intermediate risk (5-20% 10-year ASCVD risk):

   • Primary target population for CAC scoring
   • Most guidelines (NLA, SCCT, ACC/AHA) strongly recommend CAC in this group 1, 2

3. High risk (>20% 10-year ASCVD risk):

   • CAC indicated for patients reluctant to accept treatment
   • Generally, immediate statin therapy is recommended without requiring CAC 1

Special Populations

• Diabetic patients:

  • For low-moderate risk diabetics (type 1 DM <35 years, type 2 DM <50 years) with <10 years duration: CAC scoring recommended
  • For long-standing diabetes (type 1 >20 years, type 2 >10 years): immediate statin therapy without requiring CAC 1

• Women:

  • Women generally develop CAC approximately 10 years later than men
  • Same age recommendations apply, but interpretation may differ 2

• Older adults (>75 years):

  • CAC may be more valuable than age alone for risk discrimination
  • Particularly useful when deciding whether to initiate statin therapy 3

Interpretation and Follow-up

CAC scores are interpreted as follows:

• CAC = 0: Very low risk, consider deferring statin
• CAC 1-99: Mildly increased risk, consider statin (especially after age 55)
• CAC 100-299: Moderately increased risk, initiate statin therapy
• CAC ≥300: Severely increased risk, high-intensity statin recommended 1, 2

Follow-up intervals:

• CAC = 0: Repeat in 5-7 years
• CAC 1-99: Repeat in 3-5 years
• CAC ≥100 or diabetes: Repeat in 3 years 2

Clinical Pitfalls to Avoid

1. Don't use CAC for symptomatic patients - CAC is primarily for risk assessment in asymptomatic individuals

2. Don't down-classify risk in diabetic patients with CAC = 0 - They may have non-calcified plaques 1

3. Don't repeat CAC too frequently - For CAC = 0, waiting at least 5 years is recommended 1

4. Don't ignore traditional risk factors - CAC should supplement, not replace traditional risk assessment 2

5. Don't use CAC for patients with established ASCVD - These patients already warrant aggressive therapy 2

The evidence strongly supports CAC scoring as a valuable tool for cardiovascular risk assessment, particularly in intermediate-risk individuals aged 40-75, with selective use in younger individuals with significant risk factors. CAC scoring provides superior risk discrimination compared to traditional risk factors alone and can guide decisions about preventive therapies.