Do you use the 10-year risk or the average 10-year risk calculation, such as the Pooled Cohort Equations (PCE), to guide statin therapy decisions?

Using the 10-Year ASCVD Risk Calculation for Statin Therapy Decisions

The 10-year atherosclerotic cardiovascular disease (ASCVD) risk calculation using the Pooled Cohort Equations (PCE) should be used to guide statin therapy decisions, not the average 10-year risk calculation. 1

Understanding Risk Assessment for Statin Therapy

The American College of Cardiology/American Heart Association (ACC/AHA) guidelines recommend using the Pooled Cohort Equations to calculate the 10-year risk of ASCVD events to guide statin therapy decisions, particularly for primary prevention. This risk assessment tool incorporates:

• Age, sex, race
• Total cholesterol and HDL cholesterol levels
• Systolic blood pressure and antihypertensive treatment status
• Diabetes status
• Smoking status

Risk Thresholds for Statin Therapy

The guidelines establish specific risk thresholds for statin therapy initiation:

1. ≥7.5% 10-year ASCVD risk: Moderate- or high-intensity statin therapy recommended 1
2. 5% to <7.5% 10-year ASCVD risk: Consider moderate-intensity statin therapy 1
3. <5% 10-year ASCVD risk: Generally no statin therapy unless other high-risk features present 1

The US Preventive Services Task Force (USPSTF) uses slightly different thresholds:

• ≥10% 10-year ASCVD risk: Recommend statin therapy (B recommendation) 1, 2
• 7.5% to <10% 10-year ASCVD risk: Selectively offer statin therapy (C recommendation) 1, 2

Clinical Application of Risk Assessment

The PCE risk calculation should be used as the starting point for a clinician-patient discussion, not as an automatic trigger for statin initiation 1. This discussion should include:

• Potential benefits for ASCVD risk reduction
• Potential adverse effects and drug-drug interactions
• Patient preferences regarding medication use

Additional Risk Enhancers to Consider

When risk-based decisions are uncertain, especially for patients with borderline or intermediate risk, consider these additional factors:

• LDL-C ≥160 mg/dL
• Family history of premature ASCVD
• High-sensitivity C-reactive protein ≥2.0 mg/L
• Coronary artery calcium score >300 Agatston units
• Ankle-brachial index <0.9
• Elevated lifetime ASCVD risk 1, 3

Important Considerations and Potential Pitfalls

Limitations of the Pooled Cohort Equations

1. Potential overestimation: Some studies suggest the PCE may overestimate risk in certain populations, particularly those with higher socioeconomic status or those engaged with preventive healthcare services 4

2. Potential underestimation: The PCE may underestimate risk in patients from certain racial/ethnic groups, those with lower socioeconomic status, or those with chronic inflammatory diseases 4

3. Racial differences: The PCE can generate substantially different risk estimates for Black versus White individuals with identical risk profiles, which could introduce variations in clinical recommendations 5

4. Age effects: Age heavily influences risk calculation, potentially leading to statin recommendations for many older adults even without other risk factors 1

Recent Developments

The Predicting Risk of Cardiovascular Disease Events (PREVENT) equations were developed in 2023 as an update to the 2013 PCE. These newer equations:

• Remove race as a variable
• Add kidney function and statin use as variables
• Generally produce lower risk estimates than the PCE
• Could reduce the number of adults meeting criteria for primary prevention statin therapy 6

Conclusion

When making decisions about statin therapy, use the 10-year ASCVD risk calculation via the Pooled Cohort Equations as recommended by current guidelines. This approach provides a standardized method for estimating cardiovascular risk and helps identify patients most likely to benefit from statin therapy based on their absolute risk of experiencing cardiovascular events.