Coronary Artery Calcium and Long-Term€Risk of Death, Myocardial€Infarction, and Stroke

Fro Ba Mi Mi con rep Ma OBJECTIVES This study aimed to assess the long-term risk of death and atherosclerotic cardiovascular disease (ASCVD) outcomes, including stroke, in a real-world cohort that underwent coronary artery calcium (CAC) scoring. BACKGROUND Large-scale, long-term studies assessing the independent relationship of CAC for prediction of ASCVD events, to include stroke, in young, low-risk patients are uncommon outside of the clinical trial setting. METHODS A total of 23,637 consecutive subjects without ASCVD who underwent CAC scoring from 1997 to 2009 were studied. Subjects were assessed for myocardial infarction (MI), stroke, major adverse cardiovascular events (MACE) (e.g., MI, stroke, or cardiovascular death), and all-cause mortality. Outcomes were extracted from the Military Data Repository and the National Death Index and assessed using Cox proportional hazards models, controlling for baseline risk factors, atrial fibrillation, and competing mortality. RESULTS Patients (mean age 50.0 8.5 years) were followed over a median of 11.4 years. The relative adjusted subhazard ratio (aSHR) for CAC 1 to 100, 101 to 400, and >400 was 2.2, 3.8, and 5.9 for MI; 1.2, 1.4, and 1.9 for stroke; 1.4, 2.0, and 2.8 for MACE; and 1.2, 1.5 and 2.1 for death (p < 0.0001). The addition of CAC score to risk factors significantly improved the prognostic accuracy for all outcomes by the likelihood ratio test. Area under the curve increased from 0.658 to 0.738 for MI, 0.703 to 0.704 for stroke, 0.685 to 0.705 for MACE, and 0.759 to 0.767 for mortality. Among subjects without traditional risk factors (n 1⁄4 6,208; mean age 43.8 4.4 years), the presence of any CAC (>0; n 1⁄4 848) was associated with an increased risk of MACE (aSHR: 1.67; 95% confidence interval: 1.16 to 2.39). CONCLUSIONS CAC scoring significantly improved long-term prognostic accuracy for MACE events and mortality, irrespective of age and risk factors. These results support CAC screening for improving individual ASCVD risk assessment and prevention in low-risk, young adults. (J Am Coll Cardiol Img 2017;-:-–-) Published by Elsevier on behalf of the American College of Cardiology Foundation. A therosclerotic cardiovascular disease (ASCVD) accounts for nearly one-third of all deaths in the United States (1). Current guidelines from the American Heart Association, the American College of Cardiology, and the European Society of Cardiology recommend the use of ASCVD scores that rely heavily on subject age and were m the Cardiovascular Division, Washington University School of Medi ylor College of Medicine, Houston, Texas; Internal Medicine Service litary Medical Center, Bethesda, Maryland; and the Cardiology Servic litary Medical Center, Bethesda, Maryland. The views expressed here rep strued as those of the United States Army, the Department of Defense, orted that they have no relationships relevant to the contents of paper t nuscript received July 27, 2017; revised manuscript received September 5 derived from traditional risk factors to estimate 10-year risk for incident coronary and stroke outcomes (2,3). Recent data suggest that these risk scores, derived from large populations, may lack precision when applied to individuals (4). Low-dose, noncontrast computed tomography for the detection and quantification of coronary artery calcium (CAC) cine, St. Louis, Missouri; Department of Medicine, , Department of Medicine, Walter Reed National e, Department of Medicine, Walter Reed National resent those of the authors only and are not to be or the United States Government. The authors have o disclose. , 2017, accepted September 7, 2017. ABBR EV I A T I ON S