title: Relation of carotid artery 18F-FDG uptake to C-reactive protein and Framingham risk score in a large cohort of asymptomatic adults.
abstract: We investigated the relation of carotid (18)F-FDG uptake to high-sensitivity C-reactive protein (hsCRP) and Framingham risk score (FRS) in a large cohort of asymptomatic adults.
  
  
  METHODS
  Carotid artery (18)F-FDG uptake was measured on the PET/CT scans of 1,181 asymptomatic subjects, and maximum target-to-background ratio (M-TBR) and intima-media thickness (IMT) were compared with clinical risk factors and hsCRP. The estimated 10-y risk for general cardiovascular disease was calculated by FRS.
  
  
  RESULTS
  FRS increased from 11.5% ± 7.8% to 14.8% ± 10.5% in subjects with an M-TBR ≥ 1.7, compared with < 1.7, and the odds ratio for an FRS ≥ 10% was 1.9 (95% confidence interval [CI], 1.4-2.5). Adjusting for age confirmed a significant association of M-TBR and IMT with FRS. Independent determinants of high M-TBR were abdominal fat (β coefficient [B], 1.1040; P < 0.0001), low-density lipoprotein (LDL) (B, 0.0006; P < 0.05), and FRS (B, 0.0025; P < 0.05) for subjects < 50 y and abdominal fat (B, 0.9740; P < 0.0001), age (B, 0.0040; P = 0.0001), LDL (B, 0.0008; P = 0.0001), and IMT (B, 0.1097; P < 0.01) for subjects ≥ 50 y. Although hsCRP also stratified subjects for FRS-based risk, no correlation was found between hsCRP and M-TBR or IMT, suggesting that they may have different inferences. Importantly, in the low-hsCRP (14.2% ± 9.7% vs. 11.3% ± 7.4%) and high-hsCRP groups (18.8% ± 14.3% vs. 13.3% ± 10.2%), FRS was significantly greater for subjects with high M-TBR than for those with low M-TBR. The odds ratio for FRS ≥ 10% between subjects with high and low M-TBR was 1.20 (95% CI, 0.90-1.60; P = 0.209) in the low-hsCRP group and 2.95 (95% CI, 1.48-5.86; P = 0.002) in the high-hsCRP group.
  
  
  CONCLUSIONS
  High carotid (18)F-FDG uptake in asymptomatic adults is associated with increased clinical risk factors and FRS. Furthermore, it appears to reflect aspects of atherosclerotic inflammation distinct from hsCRP concentration and may offer incremental information regarding cardiovascular risk.
authors.affiliation: Department of Nuclear Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Tae Soo
authors.initials: TS
authors.lastname: Noh
authors.forename: Seung-Hwan
authors.initials: SH
authors.lastname: Moon
authors.forename: Young Seok
authors.initials: YS
authors.lastname: Cho
authors.forename: Sun Pyo
authors.initials: SP
authors.lastname: Hong
authors.forename: Eun Jeong
authors.initials: EJ
authors.lastname: Lee
authors.forename: Joon Young
authors.initials: JY
authors.lastname: Choi
authors.forename: Byung-Tae
authors.initials: BT
authors.lastname: Kim
authors.forename: Kyung-Han
authors.initials: KH
authors.lastname: Lee
mesh_terms: D000328:Adult; D000368:Aged; D058070:Asymptomatic Diseases; D001692:Biological Transport; D002097:C-Reactive Protein / Q000378:metabolism*; D002339:Carotid Arteries / Q000000981:diagnostic imaging* / Q000378:metabolism; D015331:Cohort Studies; D005260:Female; D019788:Fluorodeoxyglucose F18 / Q000378:metabolism*; D006801:Humans; D008297:Male; D008875:Middle Aged; D064847:Multimodal Imaging; D049268:Positron-Emission Tomography; D012189:Retrospective Studies; D018570:Risk Assessment; D014057:Tomography, X-Ray Computed
chemical_list: D019788:Fluorodeoxyglucose F18; D002097:C-Reactive Protein
keywords: 18F-FDG; Framingham risk score; atherosclerosis; carotid artery; hsCRP