title: A peripheral blood gene expression score is associated with atherosclerotic Plaque Burden and Stenosis by cardiovascular CT-angiography: results from the PREDICT and COMPASS studies.
abstract: OBJECTIVE
  We previously validated a gene expression score (GES) based on age, sex and peripheral blood cell expression levels of 23 genes measured by quantitative real-time PCR (qRT-PCR) for diagnosis of obstructive coronary artery disease (CAD) (≥ 50% luminal diameter stenosis). In this study we sought to determine the association between the GES and coronary arterial Plaque Burden and Stenosis by CT-angiography.
  
  
  METHODS
  A total of 610 patients (mean age: 57 ± 11; 50% male) from the PREDICT and COMPASS studies from 59 centers were analyzed. Coronary artery calcium (CAC) scoring, CT angiography (CTA)-based plaque and stenosis and GES measurements were performed. CAC was expressed as Agatston score and CTA evaluated for stenosis severity: 0. None; 1. Minimal, 2. Mild, 3. Moderate, 4. Severe and 5. Occluded. Correlation analysis, one-way analysis of variance (ANOVA) and receiver operating characteristics (ROC) analyses were performed.
  
  
  RESULTS
  GES was significantly associated with plaque burden by CAC (r = 0.50; p < 0.001) and CTA (segment involvement score index: r = 0.37, p < 0.001); a low score (≤ 15) had sensitivity of 0.71 and a high score (≥ 28) a specificity of 0.97 for the prediction of zero vs. non-zero CAC. Increasing GES was associated with a greater degree of categorical stenosis by ANOVA (p < 0.001); GES significantly correlated with maximum luminal stenosis (r = 0.41; p < 0.01) and segment stenosis score index (r = 0.38; p < 0.01). A low score had sensitivity of 0.90 and a high score a specificity of 0.87 for ≥ 70% stenosis.
  
  
  CONCLUSIONS
  A previously validated GES is significantly associated with Plaque Burden and Stenosis by CT.
  
  
  BACKGROUND
  (PREDICT [NCT00500617] and COMPASS [NCT01117506]), www.clinicaltrials.gov.
authors: Stony Brook University, Stony Brook, NY, USA.
authors: Szilard
authors: S
authors: Voros
authors: CardioDx, Inc., 2500 Faber Place, Palo Alto, CA 94303, USA.
authors: Michael R
authors: MR
authors: Elashoff
authors: CardioDx, Inc., 2500 Faber Place, Palo Alto, CA 94303, USA.
authors: James A
authors: JA
authors: Wingrove
authors: Harbor UCLA Medical Center, Torrance, CA, USA.
authors: Matthew J
authors: MJ
authors: Budoff
authors: Long Beach Memorial Medical Center, Long Beach, CA, USA; University of California, Irvine, Orange, CA, USA.
authors: Gregory S
authors: GS
authors: Thomas
authors: CardioDx, Inc., 2500 Faber Place, Palo Alto, CA 94303, USA. Electronic address: srosenberg@cardiodx.com.
authors: Steven
authors: S
authors: Rosenberg
mesh_terms: D000368:Aged; D002114:Calcinosis / Q000000981:diagnostic imaging; D003251:Constriction, Pathologic / Q000473:pathology; D017023:Coronary Angiography / Q000379:methods; D003324:Coronary Artery Disease / Q000097:blood* / Q000000981:diagnostic imaging; D003331:Coronary Vessels / Q000378:metabolism; D017281:Cost of Illness; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D058226:Plaque, Atherosclerotic / Q000473:pathology* / Q000503:physiopathology; D014057:Tomography, X-Ray Computed / Q000379:methods; D059467:Transcriptome
keywords: CT-angiography; Calcium score; Coronary artery disease; Gene expression; Plaque burden