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

Abstract

OBJECTIVE:

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.

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 Aβ 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 Aβ-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 Aβ-positive relative to Aβ-negative participants (ps < 0.05).

CONCLUSIONS:

Highly prevalent Aβ 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 Aβ-status groups may be detectable 7-9 years before neuroimaging.

• Authors: Beth E Snitz, Lisa A Weissfeld, Oscar L Lopez, Lewis H Kuller, Judith Saxton, Dilrukshika M Singhabahu, William E Klunk, Chester A Mathis, Julie C Price, Diane G Ives, Ann D Cohen, Eric McDade, Steven T Dekosky
• Journal: Neurology (Neurology) Vol. 80 Issue 15 Pg. 1378-84 (Apr 09 2013) ISSN: 1526-632X [Electronic] United States
• PMID: 23516317 (Publication Type: Journal Article, Multicenter Study, Research Support, N.I.H., Extramural)

Chemical References

• 2-(4'-(methylamino)phenyl)-6-hydroxybenzothiazole
• Amyloid beta-Peptides
• Aniline Compounds
• Plant Preparations
• Thiazoles

Topics

• Aged
• Aged, 80 and over
• Amyloid beta-Peptides (metabolism)
• Aniline Compounds
• Cognition Disorders (complications, drug therapy)
• Cross-Sectional Studies
• Dementia (diagnostic imaging, etiology, prevention & control)
• Double-Blind Method
• Female
• Ginkgo biloba
• Humans
• Linear Models
• Longitudinal Studies
• Magnetic Resonance Imaging
• Male
• Neuropsychological Tests
• Phytotherapy (methods)
• Plant Preparations (therapeutic use)
• Positron-Emission Tomography
• Psychiatric Status Rating Scales
• Retrospective Studies
• Thiazoles