Reclassification of coronary heart disease risk in a primary prevention setting: traditional risk factor assessment vs . coronary artery calcium scoring

In the last 50 years, improved understanding and treatment of the atherosclerotic risk factors have resulted in significant improvements in cardiovascular (CV) mortality (CVD) (1,2). This has resulted in development of various coronary heart disease (CHD) risk prediction scores that allow recognition of individuals at risk of future events (3-8). Many of the currently recommended risk assessment tools use traditional risk factors such as the recently developed atherosclerotic cardiovascular disease (ASCVD) risk calculator which relies upon age, gender, smoking status, diabetes, hyperlipidemia and race, parameters which were identified in the seminal Framingham study (4,6). Other studies have shown that family history of premature CHD and vascular inflammation are also crucial in risk prediction of future events. As a result, other tools such as the Reynolds Risk Score (RRS) have been developed which incorporate these predictors, and have been shown to further help in reducing residual risk of future events; in both men and women (7,8). However, despite these advances and our improved ability to identify those at increased risk of CV events, a substantial group of individuals still develop CHD events despite the absence of conventional CV risk factors. For instance, in a pooled analysis of 122,458 patients from 14 international randomized controlled trials 19% men and 15% women with a CHD event lacked traditional risk factors (9)