ASCVD Risk Calculator (2013 ACC/AHA)

About the ASCVD Risk Estimator

The 2013 ACC/AHA guideline for the assessment of cardiovascular risk introduces the pooled cohort equations to enable health care providers and patients to estimate 10-year and lifetime risks for atherosclerotic cardiovascular disease (ASCVD). ASCVDs are defined as coronary death or nonfatal myocardial infarction, or fatal or nonfatal stroke. This ASCVD risk estimator is seen by some as an adequate replacement of the Framingham Risk Score.

The information required to estimate ASCVD risk includes age (calculator restricted to 40-75 years interval), sex, race, total cholesterol, HDL cholesterol, systolic blood pressure, use of blood pressure lowering medication, diabetes status, and smoking status.

The Pooled Cohort Equations were developed and validated among Caucasian and African American men and women who did not have clinical ASCVD. At the moment, there are inadequate data for other racial groups, for which the current guidelines suggest to the use of the “Caucasian” race to estimate ASCVD risk.

The risk of ASCVD is generally lower among Hispanic and Asian populations and generally higher among American-Indian populations than that of Caucasian populations.

The Pooled Cohort Equations can be used to estimate primary cardiovascular risk and potential benefit from statin therapy. Patients are considered to be at "elevated" risk and recommended moderate- or high-intensity statin therapy if the predicted risk is 7.5% or greater.

The scoring method behind the 10-year ASCVD risk estimator, the Pooled Cohort Equations, can be found in Appendix 7 of the 2013 ACC/AHA Guideline, whilst the “10-year cardiovascular risk if risk factors were optimal” result uses the same scoring method, (for the same age, gender and race) with the following optimal values:

• Total cholesterol of 170 mg/dL
• HDL-cholesterol of 50 mg/dL
• Untreated systolic blood pressure of 110 mm Hg
• No diabetes history
• Not a current smoker

Subsequent validations studies have found that either the 10-year risk prediction is accurate r that the score substantially over-estimates the ASCVD risk.

Statin therapy for reducing cardiovascular risk

AHA/ACC guidelines stress the importance of lifestyle modifications (diet, exercise, smoking cessation) to lower cardiovascular disease risk in all patients.

NCEP ATP III guidelines for high blood cholesterol in adults recommend that the following four groups of patients will benefit from moderate- or high-intensity statin therapy:

• Individuals with clinical ASCVD;
• Individuals with primary elevations of LDL ≥ 190 mg/dL;
• Individuals 40 to 75 years of age with diabetes and an LDL 70 to 189 mg/dL without clinical ASCVD;
• Individuals without clinical ASCVD or diabetes who are 40 to 75 years of age with LDL 70 to 189 mg/dL and a 10-year ASCVD risk of 7.5% or higher.

Similarly, the 2013 American College of Cardiology (ACC) and the American Heart Association (AHA) guidelines for the evaluation and treatment of cholesterol in order to reduce the risk of atherosclerotic cardiovascular disease, also recommend moderate- to high-intensity statin treatment in patients with 10-year ASCVD risk of 7.5% of higher.

Patient with known known ASCVD and patients with extreme LDL levels (≥190 mg/dL / 4.92 mmol/L) are at the highest risk and must be started on high-intensity statins.

Examples of high-intensity statin therapy include:

• Atorvastatin (Lipitor) 80 mg (40 mg less preferred);
• Rosuvastatin (Crestor) 20-40 mg.

Examples of moderate-intensity statin therapy include:

• Atorvastatin (Lipitor) 10-20 mg;
• Rosuvastatin (Crestor) 5-10 mg;
• Simvastatin (Zocor) 20-40 mg;
• Lovastatin (Mevacor) 40 mg;
• Fluvastatin (Lescol) 40 mg (BID);
• Pravastatin (Pravachol) 40-80 mg;
• Fluvastatin XL (Lescol XL) 80 mg;
• Pitavastatin (Livalo) 2-4 mg.

References

Original reference

Goff et al. 2013 ACC/AHA Guideline on the Assessment of  Cardiovascular Risk. A Report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines

Validation

Henderson K, Kaufman BG, Stearns S, et al. Validation of the Atherosclerotic Cardiovascular Disease (ASCVD) Pooled Cohort Risk Equations by Education Level: The Atheroschlerosis Risk in Communities (ARIC) Study. J Am Coll Cardiol. 2016;67(13_S):1842. doi:10.1016/S0735-1097(16)31843-5.

Other references

Stone NJ et al. 2013 ACC/AHA Guideline on the Treatment of Blood Cholesterol to Reduce Atherosclerotic Cardiovascular Risk in Adults. A Report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines

Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults. Executive Summary of The Third Report of The National Cholesterol Education Program (NCEP) Expert Panel on Detection, Evaluation, And Treatment of High Blood Cholesterol In Adults (Adult Treatment Panel III). JAMA. 2001 May 16;285(19):2486-97