title: Effects of age and cardiovascular risk factors on (18)F-FDG PET/CT quantification of atherosclerosis in the aorta and peripheral arteries.
abstract: OBJECTIVE
  To quantify fluorine-18 fluorodeoxyglucose ((18)F-FDG) uptake in the aorta and peripheral arteries and assess the variation of (18)F-FDG uptake with age and cardiovascular risk factors.
  
  
  METHODS
  The subject population of this retrospective study comprises melanoma patients who underwent whole-body (18)F-FDG PET/CT scans. The patients' medical records were examined for cardiovascular risk factors and for a history of coronary artery disease or peripheral artery disease. Fluorine-18-FDG uptake in the peripheral arteries (iliac and femoral) and aorta was semi-quantified as a weighted-average mean standardized uptake value (wA-SUVmean), while background noise was accounted for by measuring mean venous blood pool SUV (V-SUVmean) in the superior vena cava. Atherosclerosis was semi-quantified by the tissue-to-background ratio (TBR) (wA-SUVmean divided by V-SUVmean). A regression model and t-test were used to evaluate the effect of age and location on the degree of atherosclerosis. To assess the effect of cardiovascular risk factors on atherosclerotic burden, the wA-SUVmean of patients with at least one of these risk factors was compared to that of patients without any risk factors.
  
  
  RESULTS
  A total of 76 patients (46 men, 30 women; 22-91 years old) were included in this study. The average TBR of the aorta and peripheral arteries were 2.68 and 1.43, respectively, and increased with age in both locations. In regression analysis, the beta coefficients of age for TBR in the aorta and peripheral arteries were 0.55 (P<0.001) and 0.03 (P<0.001), respectively. In all age groups, the TBR of the aorta was significantly greater than that of the peripheral arteries. The Pearson correlation coefficients between the four age groups and the TBR of the aorta and peripheral arteries were 0.83 (P<0.001) and 0.75 (P<0.001), respectively. The wA-SUVmean of patients with cardiovascular risk factors was only significant (P<0.05) in the aorta.
  
  
  CONCLUSIONS
  An increase in (18)F-FDG uptake was observed in the peripheral arteries and aorta with increasing age. Cardiovascular risk factors were significantly correlated with (18)F-FDG uptake in aorta. The early detection of atherosclerosis with (18)F-FDG PET may allow for the initiation of preventative interventions prior to the manifestation of significant structural abnormalities or symptoms of disease.
authors: Department of Radiology, Hospital of the University of Pennsylvania, Philadelphia, 3400 Spruce Street, PA 19104, USA. abass.alavi@uphs.upenn.edu.
authors: Ahmed K
authors: AK
authors: Pasha
authors: Mateen
authors: M
authors: Moghbel
authors: Babak
authors: B
authors: Saboury
authors: Mohammed H
authors: MH
authors: Gharavi
authors: Björn A
authors: BA
authors: Blomberg
authors: Drew A
authors: DA
authors: Torigian
authors: Thomas C
authors: TC
authors: Kwee
authors: Sandip
authors: S
authors: Basu
authors: Emile R
authors: ER
authors: Mohler Iii
authors: Abass
authors: A
authors: Alavi
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D001011:Aorta / Q000000981:diagnostic imaging* / Q000473:pathology; D001158:Arteries / Q000000981:diagnostic imaging*; D050197:Atherosclerosis / Q000000981:diagnostic imaging* / Q000532:radiotherapy; D002318:Cardiovascular Diseases / Q000000981:diagnostic imaging*; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008297:Male; D008545:Melanoma / Q000000981:diagnostic imaging*; D008875:Middle Aged; D049268:Positron-Emission Tomography; D019275:Radiopharmaceuticals; D012189:Retrospective Studies; D012307:Risk Factors; D014057:Tomography, X-Ray Computed; D055815:Young Adult
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18