Gender differences in cerebral glucose metabolism: a PET study.
OBJECTIVE
Some studies have examined gender differences in brain function based on cerebral blood flow and cerebral metabolism by using positron emission tomography (PET). However, the findings of these studies are controversial and most of them were analyzed by the regions of interest (ROIs) method. Here, we evaluated gender differences of cerebral glucose metabolism under the resting state in a voxel-based analysis.


METHODS
We studied 44 healthy volunteers (22 females, 63.0+/-6.3 years, and 22 males, 63.1+/-8.4 years). Cerebral glucose metabolic images were obtained with (18)F-fluorodeoxyglucose (FDG) and PET. All individual data were transformed to standard brain space and the male and female groups were compared using statistical parametric mapping (SPM).


RESULTS
The males had significantly higher glucose metabolism in the right insula, middle temporal gyrus, and medial frontal lobe than the females. Glucose metabolism in the hypothalamus was significantly higher in females than in males. There was a significant correlation between aging and glucose metabolism in the left thalamus in males and in the left caudate nucleus and hypothalamus in females. In males, but not females, there was a significant asymmetry between the bilateral hemispheres.


CONCLUSIONS
We found that there were obvious gender differences in regional cerebral glucose metabolism and this is the first report of higher glucose metabolism in the hypothalamus in females than in males.
Kawachi
Takashi
T
Division of Imaging Research, Hyogo Institute for Aging Brain and Cognitive Disorders, 520 Saisho-Ko, Himeji, Hyogo 670-0981, Japan.
Ishii
Kazunari
K
Sakamoto
Setsu
S
Matsui
Mieko
M
Mori
Tetsuya
T
Sasaki
Masahiro
M
D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000378:metabolism; D001921:Brain / Q000000981:diagnostic imaging* / Q000378:metabolism*; D002421:Caudate Nucleus / Q000000981:diagnostic imaging / Q000378:metabolism; D002540:Cerebral Cortex / Q000000981:diagnostic imaging / Q000378:metabolism; D005260:Female; D005625:Frontal Lobe / Q000000981:diagnostic imaging / Q000378:metabolism; D005947:Glucose / Q000378:metabolism*; D006801:Humans; D007031:Hypothalamus / Q000000981:diagnostic imaging / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D012016:Reference Values; D012737:Sex Factors; D013702:Temporal Lobe / Q000000981:diagnostic imaging / Q000378:metabolism; D013788:Thalamus / Q000000981:diagnostic imaging / Q000378:metabolism; D014055:Tomography, Emission-Computed
D005947:Glucose