Brain structure and function as mediators of the effects of amyloid on memory.

ABSTRACT: OBJECTIVE:The objective of this study was to test whether effects of β-amyloid (Aβ) pathology on episodic memory were mediated by metabolism and gray matter volume in the early stages of Alzheimer disease. METHODS:This was a prospective cohort study. We measured baseline Aβ (using florbetapir-PET), brain function (using fluorodeoxyglucose-PET), and brain structure (using MRI). A mediation analysis was performed to test whether statistical effects of Aβ positivity on cross-sectional and longitudinal episodic memory were mediated by hypometabolism or regional gray matter volume in cognitively healthy controls (CN, n = 280) and mild cognitive impairment (MCI, n = 463). RESULTS:Lower memory scores were associated with Aβ positivity (CN, mildly; MCI, strongly), smaller gray matter volumes (CN,

SUBMITTER: Mattsson N 

PROVIDER: S-EPMC4371407 | biostudies-literature | 2015 Mar

REPOSITORIES: biostudies-literature