Association of Gray Matter Atrophy with Age, beta-Amyloid, and Cognition in Aging

作者：Oh Hwamee^*; Madison Cindee; Villeneuve Sylvia; Markley Candace; Jagust William J

来源：Cerebral Cortex, 2014, 24(6): 1609-1618.

DOI：10.1093/cercor/bht017

• aging
• amyloid
• cognition
• Pittsburgh compound B-positron emission tomography
• structure

Both cognitive aging and beta-amyloid (A beta) deposition, a pathological hallmark of Alzheimer's disease, are associated with structural and cognitive changes in cognitively normal older people. To examine independent effects of age and A beta deposition on cognition and brain structure in aging, 83 cognitively normal older adults underwent structural magnetic resonance imaging scans and neuropsychological tests and were classified as negative (PIB-) or positive (PIB+) for A beta deposition using the radiotracer Pittsburgh compound B (PIB). Weighted composite discriminant scores represented subjects' cognition. Older adults showed age-related gray matter (GM) atrophy across the whole brain regardless of A beta deposition. Amyloid burden within PIB+ subjects, however, was associated with GM atrophy in the frontal, parietal, and temporal cortices. Associations between cognition and volume in PIB- subjects were primarily seen throughout frontal regions and the striatum, while, in PIB+ subjects, these associations were seen in orbital-frontal and hippocampal regions. Furthermore, in PIB- subjects, cognition was related to putaminal volume, but not to hippocampus, while, in PIB+ subjects, cognition was related to hippocampal volume, but not to putamen. These findings highlight differential age and A beta effects on brain structure, indicating effects of age and A beta that operate somewhat independently to affect frontostriatal and medial temporal brain systems.

• 出版日期2014-6