title: Association of Coronary Artery Calcium in Adults Aged 32 to 46 Years With Incident Coronary Heart Disease and Death.
abstract: Coronary artery calcium (CAC) is associated with coronary heart disease (CHD) and cardiovascular disease (CVD); however, prognostic data on CAC are limited in younger adults.
  
  
  
  To determine if CAC in adults aged 32 to 46 years is associated with incident clinical CHD, CVD, and all-cause mortality during 12.5 years of follow-up.
  
  
  
  The Coronary Artery Risk Development in Young Adults (CARDIA) Study is a prospective community-based study that recruited 5115 black and white participants aged 18 to 30 years from March 25, 1985, to June 7, 1986. The cohort has been under surveillance for 30 years, with CAC measured 15 (n = 3043), 20 (n = 3141), and 25 (n = 3189) years after recruitment. The mean follow-up period for incident events was 12.5 years, from the year 15 computed tomographic scan through August 31, 2014.
  
  
  
  Incident CHD included fatal or nonfatal myocardial infarction, acute coronary syndrome without myocardial infarction, coronary revascularization, or CHD death. Incident CVD included CHD, stroke, heart failure, and peripheral arterial disease. Death included all causes. The probability of developing CAC by age 32 to 56 years was estimated using clinical risk factors measured 7 years apart between ages 18 and 38 years.
  
  
  
  At year 15 of the study among 3043 participants (mean [SD] age, 40.3 [3.6] years; 1383 men and 1660 women), 309 individuals (10.2%) had CAC, with a geometric mean Agatston score of 21.6 (interquartile range, 17.3-26.8). Participants were followed up for 12.5 years, with 57 incident CHD events and 108 incident CVD events observed. After adjusting for demographics, risk factors, and treatments, those with any CAC experienced a 5-fold increase in CHD events (hazard ratio [HR], 5.0; 95% CI, 2.8-8.7) and 3-fold increase in CVD events (HR, 3.0; 95% CI, 1.9-4.7). Within CAC score strata of 1-19, 20-99, and 100 or more, the HRs for CHD were 2.6 (95% CI, 1.0-5.7), 5.8 (95% CI, 2.6-12.1), and 9.8 (95% CI, 4.5-20.5), respectively. A CAC score of 100 or more had an incidence of 22.4 deaths per 100 participants (HR, 3.7; 95% CI, 1.5-10.0); of the 13 deaths in participants with a CAC score of 100 or more, 10 were adjudicated as CHD events. Risk factors for CVD in early adult life identified those above the median risk for developing CAC and, if applied, in a selective CAC screening strategy could reduce the number of people screened for CAC by 50% and the number imaged needed to find 1 person with CAC from 3.5 to 2.2.
  
  
  
  The presence of CAC among individuals aged between 32 and 46 years was associated with increased risk of fatal and nonfatal CHD during 12.5 years of follow-up. A CAC score of 100 or more was associated with early death. Adults younger than 50 years with any CAC, even with very low scores, identified on a computed tomographic scan are at elevated risk of clinical CHD, CVD, and death. Selective use of screening for CAC might be considered in individuals with risk factors in early adulthood to inform discussions about primary prevention.
authors.affiliation: Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, Tennessee.
authors.forename: John Jeffrey
authors.initials: JJ
authors.lastname: Carr
authors.affiliation: Division of Epidemiology and Community Health, School of Public Health, University of Minnesota, Minneapolis.
authors.forename: David R
authors.initials: DR
authors.lastname: Jacobs
authors.affiliation: Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, Tennessee.
authors.forename: James G
authors.initials: JG
authors.lastname: Terry
authors.affiliation: Center for Health Metrics and Evaluation, American Heart Association, Dallas, Texas.
authors.forename: Christina M
authors.initials: CM
authors.lastname: Shay
authors.affiliation: Division of Research, Kaiser Permanente, Oakland, California.
authors.forename: Stephen
authors.initials: S
authors.lastname: Sidney
authors.affiliation: Department of Preventive Medicine, Northwestern University Feinberg School of Medicine, Chicago, Illinois.
authors.forename: Kiang
authors.initials: K
authors.lastname: Liu
authors.affiliation: Division of Epidemiology and Community Health, School of Public Health, University of Minnesota, Minneapolis.
authors.forename: Pamela J
authors.initials: PJ
authors.lastname: Schreiner
authors.affiliation: Division of Preventive Medicine, Department of Medicine, University of Alabama at Birmingham.
authors.forename: Cora E
authors.initials: CE
authors.lastname: Lewis
authors.affiliation: Division of Preventive Medicine, Department of Medicine, University of Alabama at Birmingham.
authors.forename: James M
authors.initials: JM
authors.lastname: Shikany
authors.affiliation: Division of Cardiovascular Sciences, National Heart, Lung, and Blood Institute, Bethesda, Maryland.
authors.forename: Jared P
authors.initials: JP
authors.lastname: Reis
authors.affiliation: Department of Epidemiology, Colorado School of Public Health, Aurora.
authors.forename: David C
authors.initials: DC
authors.lastname: Goff
mesh_terms: D000293:Adolescent; D000328:Adult; D050197:Atherosclerosis / Q000175:diagnosis* / Q000378:metabolism / Q000401:mortality; D002118:Calcium / Q000378:metabolism*; D017023:Coronary Angiography / Q000379:methods; D003324:Coronary Artery Disease / Q000175:diagnosis* / Q000378:metabolism / Q000401:mortality; D003331:Coronary Vessels / Q000000981:diagnostic imaging* / Q000378:metabolism; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D018570:Risk Assessment; D012307:Risk Factors; D015996:Survival Rate / Q000639:trends; D014057:Tomography, X-Ray Computed; D014481:United States / Q000453:epidemiology; D055815:Young Adult
chemical_list: D002118:Calcium