title: Measurement of arterial activity on routine FDG PET/CT images improves prediction of risk of future CV events.
abstract: OBJECTIVE
  This study sought to determine whether arterial inflammation measured by (18)F-fluorodeoxyglucose positron emission tomography ((18)F-FDG-PET) improves prediction of cardiovascular disease (CVD) beyond traditional risk factors.
  
  
  BACKGROUND
  It is unknown whether arterial (18)F-FDG uptake measured with routine PET imaging provides incremental value for predicting CVD events beyond Framingham risk score (FRS).
  
  
  METHODS
  We consecutively identified 513 individuals from 6,088 patients who underwent (18)F-FDG-PET and computed tomography (CT) imaging at Massachusetts General Hospital between 2005 and 2008 and who met additional inclusion criteria: ≥30 years of age, no prior CVD, and free of cancer. CVD events were independently adjudicated, while blinded to clinical data, using medical records to determine incident stroke, transient ischemic attack, acute coronary syndrome, revascularization, new-onset angina, peripheral arterial disease, heart failure, or CVD death. FDG uptake was measured in the ascending aorta (as target-to-background-ratio [TBR]), while blinded to clinical data.
  
  
  RESULTS
  During follow-up (median 4.2 years), 44 participants developed CVD (2 per 100 person-years at risk). TBR strongly predicted subsequent CVD independent of traditional risk factors (hazard ratio: 4.71; 95% confidence interval [CI]: 1.98 to 11.2; p < 0.001) and (hazard ratio: 4.13; 95% CI: 1.59 to 10.76; p = 0.004) after further adjustment for coronary calcium score. Addition of arterial PET measurement to FRS scores improved the C-statistic (mean ± standard error 0.62 ± 0.03 vs. 0.66 ± 0.03). Further, incorporation of TBR into a model with FRS variables resulted in an integrated discrimination of 5% (95% CI: 0.36 to 9.87). Net reclassification improvements were 27.48% (95% CI: 16.27 to 39.92) and 22.3% (95% CI: 11.54 to 35.42) for the 10% and 6% intermediate-risk cut points, respectively. Moreover, TBR was inversely associated with the timing of CVD (beta -0.096; p < 0.0001).
  
  
  CONCLUSIONS
  Arterial FDG uptake, measured from routinely obtained PET/CT images, substantially improved incident CVD prediction beyond FRS among individuals undergoing cancer surveillance and provided information on the potential timing of such events.
authors.affiliation: Cardiac MR PET CT Program, Department of Imaging and Division of Cardiology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts.
authors.forename: Amparo L
authors.initials: AL
authors.lastname: Figueroa
authors.affiliation: Cardiac MR PET CT Program, Department of Imaging and Division of Cardiology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts.
authors.forename: Amr
authors.initials: A
authors.lastname: Abdelbaky
authors.affiliation: Cardiac MR PET CT Program, Department of Imaging and Division of Cardiology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts; Division of Cardiology, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts.
authors.forename: Quynh A
authors.initials: QA
authors.lastname: Truong
authors.affiliation: Cardiac MR PET CT Program, Department of Imaging and Division of Cardiology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts.
authors.forename: Erin
authors.initials: E
authors.lastname: Corsini
authors.affiliation: Cardiac MR PET CT Program, Department of Imaging and Division of Cardiology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts.
authors.forename: Megan H
authors.initials: MH
authors.lastname: MacNabb
authors.affiliation: Cardiac MR PET CT Program, Department of Imaging and Division of Cardiology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts.
authors.forename: Zachary R
authors.initials: ZR
authors.lastname: Lavender
authors.affiliation: Cardiac MR PET CT Program, Department of Imaging and Division of Cardiology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts.
authors.forename: Meredith A
authors.initials: MA
authors.lastname: Lawler
authors.affiliation: Program in Nutritional Metabolism, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts.
authors.forename: Steven K
authors.initials: SK
authors.lastname: Grinspoon
authors.affiliation: Cardiac MR PET CT Program, Department of Imaging and Division of Cardiology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts.
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Brady
authors.affiliation: Center for Prevention and Wellness Research, Baptist Health South Florida, Department of Medicine, Herbert Wertheim College of Medicine, Department of Epidemiology, Robert Stempel College of Public Health, Florida International University, Miami, Florida; Ciccarone Center for Preventive Cardiology, Johns Hopkins University, Baltimore, Maryland.
authors.forename: Khurram
authors.initials: K
authors.lastname: Nasir
authors.affiliation: Cardiac MR PET CT Program, Department of Imaging and Division of Cardiology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts.
authors.forename: Udo
authors.initials: U
authors.lastname: Hoffmann
authors.affiliation: Cardiac MR PET CT Program, Department of Imaging and Division of Cardiology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts; Division of Cardiology, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts. Electronic address: atawakol@partners.org.
authors.forename: Ahmed
authors.initials: A
authors.lastname: Tawakol
mesh_terms: D000328:Adult; D000368:Aged; D001167:Arteritis / Q000000981:diagnostic imaging* / Q000401:mortality; D001900:Boston; D018450:Disease Progression; D005260:Female; D019788:Fluorodeoxyglucose F18; D006769:Hospitals, General; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D064847:Multimodal Imaging / Q000379:methods*; D049268:Positron-Emission Tomography; D011237:Predictive Value of Tests; D011379:Prognosis; D016016:Proportional Hazards Models; D019275:Radiopharmaceuticals; D012189:Retrospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D013997:Time Factors; D014057:Tomography, X-Ray Computed; D061205:Vascular Calcification / Q000000981:diagnostic imaging
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18
keywords: (18)F-FDG-PET; (18)F-fluorodeoxyglucose positron emission tomography; CAC; CT; CVD; FDG-PET; FRS; Framingham risk score; NRI; PAD; SUV; TBR; cardiovascular disease; cardiovascular events; computed tomography; coronary artery calcium; high-sensitivity C-reactive protein; hs-CRP; inflammation; net reclassification index; peripheral arterial disease; risk factors; standardized uptake value; target-to-background ratio