Dataset Information

Cognitive trajectories associated with ?-amyloid deposition in the oldest-old without dementia.

ABSTRACT:

Objective

To determine whether a high prevalence (55%) of A? deposition in a cohort of individuals remaining dementia-free into their 9th and 10th decades is associated with cognitive decline prior to imaging.

Methods

A total of 194 participants (mean age 85.5 years, range 82-95) who completed the Ginkgo Evaluation of Memory Study (GEMS) and remained dementia-free subsequently completed Pittsburgh compound B-PET imaging. We examined cross-sectional associations between A? status and performance on a broad neuropsychological test battery completed at GEMS entry 7-9 years prior to neuroimaging. We also longitudinally examined cognition over annual evaluations using linear mixed models.

Results

At GEMS screening (2000-2002), participants who were A?-positive in 2009 had lower performance on the Stroop test (p < 0.01) and Raven's Progressive Matrices (p = 0.05), with trend level difference for Block Design (p = 0.07). Longitudinal analyses showed significant slope differences for immediate and delayed recall of the Rey-Osterrieth figure, semantic fluency, and Trail-Making Test parts A and B, indicating greater performance decline prior to neuroimaging for A?-positive relative to A?-negative participants (ps < 0.05).

Conclusions

Highly prevalent A? deposition in oldest-older adults is associated with cognitive decline in visual memory, semantic fluency, and psychomotor speed beginning 7-9 years prior to neuroimaging. Mean differences in nonmemory domains, primarily executive functions, between A?-status groups may be detectable 7-9 years before neuroimaging.

SUBMITTER: Snitz BE

PROVIDER: S-EPMC3662268 | biostudies-literature | 2013 Apr

REPOSITORIES: biostudies-literature

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Publications

Cognitive trajectories associated with β-amyloid deposition in the oldest-old without dementia.

Snitz Beth E BE Weissfeld Lisa A LA Lopez Oscar L OL Kuller Lewis H LH Saxton Judith J Singhabahu Dilrukshika M DM Klunk William E WE Mathis Chester A CA Price Julie C JC Ives Diane G DG Cohen Ann D AD McDade Eric E Dekosky Steven T ST

Neurology 20130320 15

<h4>Objective</h4>To determine whether a high prevalence (55%) of Aβ deposition in a cohort of individuals remaining dementia-free into their 9th and 10th decades is associated with cognitive decline prior to imaging.<h4>Methods</h4>A total of 194 participants (mean age 85.5 years, range 82-95) who completed the Ginkgo Evaluation of Memory Study (GEMS) and remained dementia-free subsequently completed Pittsburgh compound B-PET imaging. We examined cross-sectional associations between Aβ status a ...[more]

PMID: 23516317

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