2019 ACC/AHA Guideline on the Primary Prevention of Cardiovascular Disease

Assessment of ASCVD risk remains the foundation of primary prevention. Although all individuals should be encouraged to follow a heart-healthy lifestyle, estimating an individual’s 10-year absolute ASCVD risk enables matching the intensity of preventive interventions to the patient’s absolute risk, to maximize anticipated benefit and minimize potential harm from overtreatment. The 10-year ASCVD risk estimate is used to guide decision-making for many preventive interventions, including lipid management ( S2.2-4 , S2.2-36 ) and BP management ( S2.2-37 ); it should be the start of a conversation with the patient about risk-reducing strategies (the “clinician–patient discussion”) and not the sole decision factor for the initiation of pharmacotherapy ( S2.2-4 , S2.2-36 , S2.2-38 ). All risk estimation tools have inherent limitations, and population-based risk scores must be interpreted in light of specific circumstances for individual patients. The PCE have been shown to overestimate ( S2.2-15 , S2.2-39 – S2.2-47 ) or underestimate ( S2.2-12 , S2.2-48 – S2.2-51 ) ASCVD risk for certain subgroups. Thus, after calculation of the PCE, it is reasonable to use additional risk-enhancing factors to guide decisions about preventive interventions for borderline- or intermediate-risk adults ( S2.2-4 – S2.2-14 ). However, the value of preventive therapy may remain uncertain for many individuals with borderline or intermediate estimated 10-year risk, and some patients may be reluctant to take medical therapy without clearer evidence of increased ASCVD risk. For these individuals, the assessment of coronary artery calcium is a reasonable tool to reclassify risk either upward or downward, as part of shared decision-making. For younger adults 20 to 59 years of age, estimation of lifetime risk may be considered. For adults >75 years of age, the clinician and patient should engage in a discussion about the possible benefits of preventive therapies appropriate to the age group in the context of comorbidities and life expectancy.