According to the Centers for Disease Control and Prevention (CDC), one individual dies every 36 seconds in the United States from cardiovascular disease — the number one cause of death in the nation and a major cause of death globally. Specifically, atherosclerotic cardiovascular disease (ASCVD), which is caused by the buildup of plaques in arterial walls, can be potentially prevented by the aid of the coronary artery calcium (CAC) score.

The CAC score essentially detects and quantifies the amount of calcified plaque in the coronary arteries. A low CAC score signifies lower risk of ASCVD whereas a high CAC score signifies higher risk. In general, it is difficult to predict an ASCVD event. Today, more than 30 years after the inception of the score, there is ample support to continue using the CAC score as a decision aid when prescribing statins and potentially other preventive medications and interventions. Traditional risk factors including age, weight, blood pressure and cholesterol levels suggest some risk, but they are insufficient in accurately predicting ASCVD risk in asymptomatic individuals. There is a great need for accurate estimation and prediction of ASCVD risk to minimize cost and misallocation of health care resources. In a recent review published in the British Medical Journal, cardiologists Khurram Nasir, MD, MPH, Jerold B. Katz Investigator, Chief, Division of Cardiovascular Prevention & Wellness, and Professor of Cardiology and Miguel Cainzos-Achirica, MD, PhD, MPH, Assistant Professor of Preventive Cardiology, discuss the history of the CAC score, key studies leading to its adoption in clinical practice guidelines and its role in the personalization of risk scoring and subsequent management strategies.

The CAC score offers critical insight for downstream decision-making and disease management strategies. Notably, that could mean refraining from, or at least delaying, expensive novel therapies, especially if the patient’s calcium score is zero. A 75-year-old patient with a score of zero does not have zero risk of cardiac events but is within the lowest risk category for their age and markedly lower risk than a 75-year-old with a high score. The same applies to patients with diabetes, severe hypercholesterolemia and other features that increase the average risk of cardiovascular events. Having a CAC of zero isn't just meaningful for the patient; it's empowering for the patient's physician as well. It allows for enhanced flexibility in terms of deciding what treatments and interventions are most appropriate to keep the patient on a healthy track. According to Nasir and Cainzos-Achirica, “In a context of progressively low estimated ASCVD risk thresholds for consideration of preventive therapy with statins in international primary prevention guidelines, CAC = 0, which is associated with low event rates in several populations, has become a particularly powerful prognostic tool and may be incorporated in clinician-patient discussions to guide the safe avoidance of preventive therapy with statins and aspirin. Moving forward, ongoing studies will help define the potential role of the CAC score in informing the personalized allocation of other risk reduction therapies among several populations, such as individuals with diabetes and severe hypercholesterolemia.” Studies conducted by Nasir, among others, suggest that patients are more compliant when they have an accurate picture of their burden of plaque. It improves adherence to both lifestyle changes and medication to know how much is riding on these interventions.