Association Between Colonic 18F-FDG Uptake and Glycemic Control in Patients with Diabetes Mellitus.

PURPOSE: Positron emission tomography/computed tomography (PET/CT) with 18F-fluorodeoxyglucose (FDG) is a useful imaging modality that visualizes glucose utilization. Diffuse colonic FDG uptake is frequently observed in patients being treated for diabetes mellitus (DM), especially with metformin. The aim of this study was to evaluate whether patients without increased colonic FDG uptake after taking oral hypoglycemic agents (OHA) are associated with insufficient glycemic control.
METHODS: A total of 279 subjects who underwent FDG PET/CT scans for health examinations and had been diagnosed with DM and taken an OHA before the day of the FDG PET/CT were included. Colonic FDG uptake in the study subjects was visually assessed, and the maximal and mean standard uptake value (SUV) was measured. Fasting blood glucose and glycated hemoglobin A1c (HbA1c) levels at both baseline and follow-up visits as well as DM management were compared according to the colonic FDG uptake.
RESULTS: The mean age of study subjects was 48.8 years old, and 251 of subjects were male. Positive colonic FDG uptake was observed in 200 (71.7%) subjects. Fasting blood glucose and Hb1Ac levels on the day of FDG PET/CT were higher in subjects without positive colonic FDG uptake than those with positive colonic FDG uptake (p ≤ 0.001). But there was no significant difference between the two groups at follow-up visits.
CONCLUSIONS: Patients with DM who did not show increased colonic FDG uptake after taking OHA were associated with higher fasting blood glucose and HbA1c levels on the day of FDG PET/CT. © Korean Society of Nuclear Medicine 2020.