title: Differentiation of severe coronary artery calcification in the Multi-Ethnic Study of Atherosclerosis.
abstract: BACKGROUND
  Coronary artery calcium (CAC) scores predict coronary heart disease (CHD) risk. Little is known, however, about the distinctive risk among asymptomatic individuals with very high CAC (≥ 1000) compared to high CAC (400-999).
  
  
  RESULTS
  We compared CHD risk factors and event rates between participants with very high CAC (n = 257) and high CAC (n = 420) among adults free of clinical CHD in the Multi-Ethnic Study of Atherosclerosis (MESA). CAC was measured at baseline, and participants were followed for a median of 68 months. Very high CAC (≥ 1000), compared to high CAC (400-999), was associated with male gender (OR 3.10, p < 0.001) and older age (OR 1.42 per 10 year increase, p < 0.001). Chronic kidney disease (CKD) was associated with very high CAC (OR 1.66, p = 0.009) with a greater prevalence of moderate CKD (GFR 30-59) in the ≥ 1000 group (25% vs. 18%). Those with very high CAC were more likely to develop angina (adjusted HR 1.72 [95% CI 1.03-2.90], p = 0.04), but not more likely to experience myocardial infarction, resuscitated cardiac arrest, or CHD death (adjusted HR 1.17, [95% CI 0.64-2.12] p = 0.61) compared to high CAC. Total CHD event rates were greater for very high CAC (3.7 per 100 person-years) compared to high CAC (2.6 per 100 person-years).
  
  
  CONCLUSIONS
  Both high and very high CAC are associated with an elevated risk of CHD events in those without symptomatic CHD at baseline; however, very high CAC is associated with an increased risk of angina, but not CHD death or MI, compared to high CAC.
authors.affiliation: Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21287, United States. coylewright.megan@mayo.edu
authors.forename: Megan
authors.initials: M
authors.lastname: Coylewright
authors.forename: Kenneth
authors.initials: K
authors.lastname: Rice
authors.forename: Matthew J
authors.initials: MJ
authors.lastname: Budoff
authors.forename: Roger S
authors.initials: RS
authors.lastname: Blumenthal
authors.forename: Philip
authors.initials: P
authors.lastname: Greenland
authors.forename: Richard
authors.initials: R
authors.lastname: Kronmal
authors.forename: R Graham
authors.initials: RG
authors.lastname: Barr
authors.forename: Gregory L
authors.initials: GL
authors.lastname: Burke
authors.forename: Russell
authors.initials: R
authors.lastname: Tracy
authors.forename: Wendy S
authors.initials: WS
authors.lastname: Post
mesh_terms: D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000787:Angina Pectoris / Q000453:epidemiology; D058070:Asymptomatic Diseases; D002114:Calcinosis / Q000175:diagnosis* / Q000208:ethnology / Q000401:mortality; D016009:Chi-Square Distribution; D002908:Chronic Disease; D003324:Coronary Artery Disease / Q000175:diagnosis / Q000453:epidemiology* / Q000208:ethnology / Q000401:mortality; D003327:Coronary Disease / Q000175:diagnosis / Q000453:epidemiology* / Q000208:ethnology / Q000401:mortality; D005260:Female; D006323:Heart Arrest / Q000453:epidemiology; D006801:Humans; D007674:Kidney Diseases / Q000453:epidemiology; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000453:epidemiology; D016017:Odds Ratio; D011237:Predictive Value of Tests; D011379:Prognosis; D016016:Proportional Hazards Models; D018570:Risk Assessment; D012307:Risk Factors; D012720:Severity of Illness Index; D012737:Sex Factors; D013997:Time Factors; D014481:United States / Q000453:epidemiology