Relationship Between Alzheimer Disease-Like Pattern of 18F-FDG and Fasting Plasma Glucose Levels in Cognitively Normal Volunteers

K. Ishibashi, A. Onishi, Y. Fujiwara, K. Ishiwata, K. Ishii
2015 Journal of Nuclear Medicine  
Increased plasma glucose (PG) levels can alter the cerebral distribution pattern of 18 F-FDG uptake and reduce 18 F-FDG uptake, especially in the precuneus. The 18 F-FDG distribution pattern in cognitively normal subjects is described as an Alzheimer disease (AD)-like pattern. The aim of this study was to determine the fasting PG levels that can reduce 18 F-FDG uptake in the precuneus. Methods: Fifty-one cognitively normal volunteers (mean age ± SD, 69.7 ± 5.9 y) underwent 18 F-FDG PET scanning
more » ... and were divided into 2 groups according to the level of fasting PG at the time of PET scanning: control (n 5 31, 80 mg/dL # fasting PG , 100 mg/dL) and impaired fasting glucose (IFG) (n 5 20, 100 mg/dL # fasting PG , 110 mg/dL). 18 F-FDG uptake was compared between the 2 groups using voxelwise analyses with a global normalization method and volume-of-interest (VOI)-based analyses. VOIs were placed on the precuneus, posterior cingulate, and visual cortex, and the ratio of the uptake value on the precuneus VOI to that on the visual cortex VOI (PreCne/VC ratios) and to that on the posterior cingulate VOI (PreCne/PostCin ratios) was calculated. Results: Whole-brain voxelwise analyses showed that 18 F-FDG uptake in the precuneus was significantly lower in the IFG group (P , 0.05, familywise error rate-corrected) than in the control group. VOI analyses showed significantly lower PreCne/VC ratios (P 5 0.002) and PreCne/PostCin ratios (P 5 0.004) in the IFG group than in the control group. Conclusion: The present study confirmed that increased fasting PG levels decrease 18 F-FDG uptake, especially in the precuneus, as in the AD-like pattern. Furthermore, the study provided initial evidence that the AD-like pattern can appear even in an individual with a mildly higher level of fasting PG (100-110 mg/dL). Plasma Glucose Levels in Cognitively Normal Volunteers F-FDG and Fasting 18 Like Pattern of − Relationship Between Alzheimer Disease This article and updated information are available at: Information about subscriptions to JNM can be found at:
doi:10.2967/jnumed.114.150045 pmid:25572094 fatcat:g4anywxwvnbpboe52j3v667xiu