title: Prevalence of angiographically defined obstructive coronary artery disease in asymptomatic patients with type 2 diabetes according to the coronary calcium score.
abstract: OBJECTIVE
  The aim of this study was to determine whether the absence of coronary artery calcium (CAC) can safely exclude obstructive coronary artery disease (CAD) in asymptomatic patients with type 2 diabetes.
  
  
  METHODS
  We enrolled 478 consecutive asymptomatic patients with type 2 diabetes who visited the diabetes clinic of the Asan Medical Center between October 1, 2009 and December 31, 2010. All patients underwent 64-slice dual-source computed tomography (DSCT) for CAC scoring as well as computed tomography angiography (CTA). Patients with at least one significant coronary stenosis with >50% luminal narrowing were classified as having obstructive CAD. The findings were confirmed using conventional coronary angiography (CAG).
  
  
  RESULTS
  Among the 478 patients, 157 (33%) had a CAC score of 0 (CAC=0). Of these, 17 (11%) had obstructive CAD confirmed on CAG. The presence of CAC had a negative predictive value for obstructive CAD on CAG of 89% and a sensitivity of 88%, a specificity of 42% and a positive predictive value of 38%. A multivariate logistic regression analysis showed that current smoking habits were significantly associated with the presence of obstructive CAD in patients with CAC=0 after adjusting for traditional cardiovascular risk factors (odds ratio 4.87, 95% confidence interval 1.65-14.42, p=0.004).
  
  
  CONCLUSIONS
  Our findings suggest that CAC=0 on 64-slice DSCT cannot safely exclude obstructive CAD on CAG in asymptomatic patients with type 2 diabetes, particularly in current smokers. CTA should be combined with CAC scoring in screening for CAD in asymptomatic patients with type 2 diabetes.
authors.affiliation: Department of Internal Medicine, University of Ulsan College of Medicine, Republic of Korea.
authors.forename: Jaechan
authors.initials: J
authors.lastname: Leem
authors.forename: Eun
authors.initials: E
authors.lastname: Hee Koh
authors.forename: Eunheui
authors.initials: E
authors.lastname: Jeong
authors.forename: Jung Eun
authors.initials: JE
authors.lastname: Jang
authors.forename: Seung-Whan
authors.initials: SW
authors.lastname: Lee
authors.forename: Joon-Won
authors.initials: JW
authors.lastname: Kang
authors.forename: Tae-Hwan
authors.initials: TH
authors.lastname: Lim
authors.forename: Woo Je
authors.initials: WJ
authors.lastname: Lee
authors.forename: Min-Seon
authors.initials: MS
authors.lastname: Kim
authors.forename: Joong-Yeol
authors.initials: JY
authors.lastname: Park
authors.forename: Ki-Up
authors.initials: KU
authors.lastname: Lee
mesh_terms: D000368:Aged; D002118:Calcium / Q000378:metabolism*; D017023:Coronary Angiography; D003324:Coronary Artery Disease / Q000150:complications* / Q000000981:diagnostic imaging* / Q000453:epidemiology; D023921:Coronary Stenosis / Q000150:complications / Q000000981:diagnostic imaging / Q000453:epidemiology; D003331:Coronary Vessels / Q000000981:diagnostic imaging* / Q000378:metabolism*; D003924:Diabetes Mellitus, Type 2 / Q000150:complications*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D014057:Tomography, X-Ray Computed; D061205:Vascular Calcification / Q000150:complications / Q000000981:diagnostic imaging / Q000378:metabolism
chemical_list: D002118:Calcium