title: Associations of carotid artery intima-media thickness (IMT) with risk factors and prevalent cardiovascular disease: comparison of mean common carotid artery IMT with maximum internal carotid artery IMT.
abstract: OBJECTIVE
  The goal of this study was to compare internal carotid artery (ICA) intima-media thickness (IMT) with common carotid artery (CCA) IMT as global markers of cardiovascular disease (CVD).
  
  
  METHODS
  Cross-sectional measurements of the mean CCA IMT and maximum ICA IMT were made on ultrasound images acquired from the Framingham Offspring cohort (n = 3316; mean age, 58 years; 52.7% women). Linear regression models were used to study the associations of the Framingham risk factors with CCA and ICA IMT. Multivariate logistic regression models and receiver operating characteristic (ROC) curve analysis were used to compare the associations of prevalent CVD with CCA and ICA IMT and determine sensitivity and specificity.
  
  
  RESULTS
  The association between age and the mean CCA IMT corresponded to an increase of 0.007 mm/y; the increase was 0.037 mm/y for the ICA IMT. Framingham risk factors accounted for 28.6% and 27.5% of the variability in the CCA and ICA IMT, respectively. Age and gender contributed 23.5% to the variability of the CCA IMT and 22.5% to that of the ICA IMT, with the next most important factor being systolic blood pressure (1.9%) for the CCA IMT and smoking (1.6%) for the ICA IMT. The CCA IMT and ICA IMT were statistically significant predictors of prevalent CVD, with the ICA IMT having a larger area under the ROC curve (0.756 versus 0.695).
  
  
  CONCLUSIONS
  Associations of risk factors with CCA and ICA IMT are slightly different, and both are independently associated with prevalent CVD. Their value for predicting incident cardiovascular events needs to be compared in outcome studies.
authors.affiliation: Department of Radiology, Tufts Medical Center, Boston, MA 02111, USA. jpolak@tuftsmedicalcenter.org
authors.forename: Joseph F
authors.initials: JF
authors.lastname: Polak
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Pencina
authors.forename: Allison
authors.initials: A
authors.lastname: Meisner
authors.forename: Karol M
authors.initials: KM
authors.lastname: Pencina
authors.forename: Lisa S
authors.initials: LS
authors.lastname: Brown
authors.forename: Philip A
authors.initials: PA
authors.lastname: Wolf
authors.forename: Ralph B
authors.initials: RB
authors.lastname: D'Agostino
mesh_terms: D000328:Adult; D000369:Aged, 80 and over; D002318:Cardiovascular Diseases / Q000453:epidemiology* / Q000473:pathology*; D017536:Carotid Artery, Common / Q000000981:diagnostic imaging* / Q000473:pathology; D002343:Carotid Artery, Internal / Q000000981:diagnostic imaging* / Q000473:pathology; D005260:Female; D006801:Humans; D016014:Linear Models; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D012372:ROC Curve; D018570:Risk Assessment; D012307:Risk Factors; D017539:Tunica Intima / Q000000981:diagnostic imaging* / Q000473:pathology; D017540:Tunica Media / Q000000981:diagnostic imaging* / Q000473:pathology; D018608:Ultrasonography, Doppler