title: The 9p21 genetic variant is additive to carotid intima media thickness and plaque in improving coronary heart disease risk prediction in white participants of the Atherosclerosis Risk in Communities (ARIC) Study.
abstract: OBJECTIVE
  We evaluated whether the addition of carotid intima media thickness and plaque (CIMT-P), and a single nucleotide polymorphism on chromosome 9p21 (9p21) together improve coronary heart disease (CHD) risk prediction in the ARIC study.
  
  
  METHODS
  Ten year CHD risk was estimated using the ARIC coronary risk score (ACRS) alone and in combination with CIMT-P and 9p21 individually and together in White participants (n=9338). Area under the receiver operating characteristic curve (AUC), model calibration, net reclassification index (NRI), integrated discrimination index (IDI) and number of individuals reclassified were estimated.
  
  
  RESULTS
  The AUC of the ACRS, ACRS+9p21, ACRS+CIMT-P and ACRS+CIMT-P+9p21 models were 0.748, 0.751, 0.763 and 0.766 respectively. The percentage of individuals reclassified, model calibration, NRI and IDI improved when CIMT-P and 9p21 were added to the ACRS only model (see manuscript).
  
  
  CONCLUSIONS
  Addition of 9p21 allele information to CIMT-P minimally improves CHD risk prediction in whites in the ARIC study.
authors.affiliation: Section of Atherosclerosis and Vascular Medicine, Department of Medicine, Baylor College of Medicine, Methodist DeBakey Heart and Vascular Center, the Methodist Hospital, Houston, TX, USA. vnambi@bcm.tmc.edu
authors.forename: Vijay
authors.initials: V
authors.lastname: Nambi
authors.forename: Eric
authors.initials: E
authors.lastname: Boerwinkle
authors.forename: Kim
authors.initials: K
authors.lastname: Lawson
authors.forename: Ariel
authors.initials: A
authors.lastname: Brautbar
authors.forename: Lloyd
authors.initials: L
authors.lastname: Chambless
authors.forename: Nora
authors.initials: N
authors.lastname: Franeschini
authors.forename: Kari E
authors.initials: KE
authors.lastname: North
authors.forename: Salim S
authors.initials: SS
authors.lastname: Virani
authors.forename: Aaron R
authors.initials: AR
authors.lastname: Folsom
authors.forename: Christie M
authors.initials: CM
authors.lastname: Ballantyne
mesh_terms: D059168:Carotid Intima-Media Thickness; D002899:Chromosomes, Human, Pair 9 / Q000235:genetics*; D003327:Coronary Disease / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000209:etiology; D006801:Humans; D058226:Plaque, Atherosclerotic / Q000737:chemistry*; D020641:Polymorphism, Single Nucleotide; D012372:ROC Curve; D012306:Risk; D012307:Risk Factors; D044465:White People / Q000235:genetics