Association between age, uptake of 18 F-fluorodeoxyglucose and of 18 F-sodium fluoride, as cardiovascular risk factors in the abdominal aorta.

OBJECTIVE: We aimed to assess the feasibility of quantifying fluorine-18-fluorodexoglucose (18 F-FDG) and 18 F-sodium fluoride (18 F-NaF) uptake in abdominal aorta and examine their association with age and cardiovascular risk factors.

SUBJECTS AND METHODS: Our study comprised 123 subjects (48±14 years of age, 62 men) including 78 healthy volunteers and 45 patients with chest pain syndrome, who originally enrolled in the CAMONA study in Odense, Denmark (NCT01724749). All subjects underwent 18 F-FDG positron emission tomography/computed tomography (PET/CT) and 18 F-NaF PET/CT on separate days, 180min and 90min after administration of tracers, respectively. The global tracer uptake value (GTUV) in the abdominal aorta was determined as sum of the product of each slice area and its corresponding average standardized uptake value (SUV mean), divided by the sum of those slice areas. In addition, for each subject, the 10 years Framingham risk score (FRS) was calculated. The correlations between 18 F-NaF and 18 F-FDG GTUV with age and 10 years FRS were assessed in all, healthy and patient subjects.

RESULTS: There was a significant, positive correlation between subjects' age and 18 F-NaF GTUV (r=0.35, P<0.001), but not 18 F-FDG GTUV (r=0.06, P=0.53). Also, there was a significant, positive correlation between 10 years FRS and 18 F-NaF GTUV (r=0.30, P<0.001), but not 18 F-FDG GTUV (r=0.01, P=0.95). Individual differences in 18 F-FDG and 118 F-NaF uptake were large in both healthy subjects and patients.

CONCLUSION: In this study, the global uptake of 18 F-NaF in abdominal aorta was positively associated with age and 10 years FRS in all subjects, healthy and patient groups, whereas the global uptake of 18 F-FDG was not.