TY - JOUR T1 - Age-related brain structural changes exceed metabolic alteration in the young to middle-aged adults: The Ishikawa Brain Imaging Study JF - Journal of Nuclear Medicine JO - J Nucl Med SP - 250 LP - 250 VL - 50 IS - supplement 2 AU - Ichiro Matsunari AU - Keisuke Shima AU - Miharu Samuraki AU - Wei-Ping Chen AU - Daisuke Yanase AU - Nozomi Takeda AU - Mitsuhiro Yoshita AU - Seigo Kinuya AU - Masahito Yamada Y1 - 2009/05/01 UR - http://jnm.snmjournals.org/content/50/supplement_2/250.abstract N2 - 250 Objectives Although both brain structural and metabolic alterations occur during normal aging, their relationship in the young to middle-aged (YM) adults is unknown. Our aim was to compare age-related structural and metabolic changes in YM adults using voxel-based morphometry (VBM) and FDG PET. Methods From a pool of 782 volunteers who underwent both 3D-T1 MRI and FDG PET, we selected 160 healthy subjects (age: 23-58y, MMSE score: 29.8±0.4) to generate 4 age-specific image data sets ranging from their 20s to 50s; each consisted of 20 males and 20 females. Using SPM5, age-related reduction in FDG activity or gray-matter (GM) concentration adjusted for global brain was assessed by comparing the 20s data, which served as a reference, with the older groups. Results In their 30s, reduced GM concentration was noted in the perisylvian area, whereas such a decline was not observed in any regions by PET. In their 40s and 50s, the area of reduced GM concentration continuously expanded, and was larger than that of FDG decline. However, the area of FDG decline involved the superior frontal gyrus, and anterior cingulate, where GM concentration was spared. Conclusions Age-related reduction in GM concentration occurs as early as in their 30s, and exceeds that in metabolic activity in YM adults, suggesting that compensatory mechanisms may play a role in the area of neuronal loss. Conversely, age-related metabolic decline may occur without loss of neurons, reflecting the complex nature of aging process. ER -