title: Differences in coronary atherosclerotic plaque burden and composition according to increasing age on computed tomography angiography.
abstract: OBJECTIVE
  Few data were available regarding the underlying burden of specific plaque types with increasing ages. The aim of this study was to assess the relationship of coronary artery calcium (CAC) score with total coronary plaque burden and the difference of underlying coronary plaque composition across differing aging groups using 64-slice multidetector computed tomography.
  
  
  METHODS
  Multidetector computed tomographic images of 781 consecutive patients were evaluated using a 15-coronary segment model. Segment involvement score (the total number of segments with any plaque), segment stenosis score (the sum of maximal stenosis score per segment), total plaque score (the sum of the plaque amount per segment), and plaque composition were measured to compare with total CAC scores stratified by age tertile (lowest [n = 274], <55 years; middle [n = 242], 55-65 years; highest [n = 265], >65 years).
  
  
  RESULTS
  The mean age of the study population was 59 ± 13 years (481 men [62%]). With increasing age, higher segment involvement scores, segment stenosis scores, and total plaque scores were noted. Plaque burden was correlated significantly with total CAC scores in all tertiles. The percentage of partially calcified (P < .001) and calcified (P < .001) plaque increased with age, and in the highest age tertile, 87% of plaque contained calcium (calcified or mixed), compared to only 63% in the younger patients (P < .001). Those aged >65 years were highly unlikely to have isolated noncalcified plaque (in the setting of a calcium score of 0). Younger patients were 10 times more likely to have isolated noncalcified plaque (P < .001).
  
  
  CONCLUSIONS
  The absence of CAC strongly excludes obstructive disease, and CAC predicts the presence of coronary atherosclerotic plaque. However, the absence of any CAC does not exclude the presence of coronary atherosclerotic plaque, especially in patients aged <55 years. Plaque composition shifted from noncalcified to calcified plaque with increasing age, which may affect the vulnerability of these lesions over time.
authors.affiliation: Division of Cardiology, Kwandong University College of Medicine, Myongji Hospital, Goyang-Si, South Korea.
authors.forename: Tae-Young
authors.initials: TY
authors.lastname: Choi
authors.forename: Dong
authors.initials: D
authors.lastname: Li
authors.forename: Khurram
authors.initials: K
authors.lastname: Nasir
authors.forename: Irfan
authors.initials: I
authors.lastname: Zeb
authors.forename: Souraya
authors.initials: S
authors.lastname: Sourayanezhad
authors.forename: Mohit
authors.initials: M
authors.lastname: Gupta
authors.forename: Yalcin
authors.initials: Y
authors.lastname: Hacioglu
authors.forename: Song S
authors.initials: SS
authors.lastname: Mao
authors.forename: Matthew J
authors.initials: MJ
authors.lastname: Budoff
mesh_terms: D017677:Age Distribution; D002114:Calcinosis / Q000000981:diagnostic imaging* / Q000453:epidemiology*; D002140:California / Q000453:epidemiology; D015897:Comorbidity; D017023:Coronary Angiography / Q000706:statistics & numerical data*; D003324:Coronary Artery Disease / Q000000981:diagnostic imaging* / Q000453:epidemiology*; D005260:Female; D006801:Humans; D008297:Male; D015995:Prevalence; D015203:Reproducibility of Results; D018570:Risk Assessment; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed / Q000706:statistics & numerical data*