Cardiac Risk in Primary Prevention: From Categorical to Individual Risk

The MESA CHD risk score is the first available algorithm incorporating CAC with traditional risk factors for 10-year risk prediction.

It is based upon a large, modern, community-based multiethnic cohort with Independent validation of the model in 2 contemporary cohorts—one international from Germany and the second an U.S.-based multiethnic study—provides evidence of external validity.

It can be used by radiologists and cardiologists when interpreting and reporting CAC scores from each low dose chest CT. Scan readers can now calculate and provide a “post-test” 10-year CHD risk after CAC scanning based on the MESA risk score. This updated 10-year risk could be used to help make therapeutic decisions, such as the decision to start statin or aspirin therapy in primary prevention.

The new ACC/AHA guidelines recommended 2,377 (50%) MESA participants for moderate- to high-intensity statins; the majority (77%) was eligible because of a 10-year estimated ASCVD risk ≥7.5%.

Of those recommended statins: 41% had CAC = 0 and had 5.2 ASCVD events/1,000 P/Y

Among 589 participants (12%) considered for moderate-intensity statin, 338 (57%) had a CAC = 0, with an ASCVD event rate of 1.5 per 1,000 P/Y

Of participants eligible (recommended or considered) for statins, 44% (1,316 of 2,966) had CAC = 0 at baseline and an observed 10-year ASCVD event rate of 4.2 per 1,000 person-years.

This new approach to cardiac risk assessment should be considered in the daily clinical practice . It is time to move from categorial to the real individual risk.