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P2–101: Amyloid and vascular cognitive impairment: A pilot study of frequency and impact
Author(s) -
Dao Elizabeth,
Robin Hsiung GingYuek,
Sossi Vesna,
Jacova Claudia,
LiuAmbrose Teresa
Publication year - 2013
Publication title -
alzheimer's and dementia
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 6.713
H-Index - 118
eISSN - 1552-5279
pISSN - 1552-5260
DOI - 10.1016/j.jalz.2013.05.745
Subject(s) - cognition , dementia , stroop effect , psychology , pittsburgh compound b , vascular dementia , medicine , disease , pathology , psychiatry
Background: Traditionally, Alzheimer’s disease (AD) and vascular cognitive impairment (VCI) were considered to be distinct and unrelated; however, increasing evidence is demonstrating an overlap between AD and VCI pathology. As such, the current criteria for the clinical diagnosis of VCI may not distinguish those with cognitive impairment due to subcortical ischemic small vessel disease from those with cognitive impairment due to mixed vascular and AD pathology (mixed dementia MD). Furthermore, it is unclear how co-existing amyloid pathology may affect cognitive function in peoplewith VCI. The purpose of this pilot study was to determine the frequency of MD in patients diagnosed with VCI. In addition, we investigated how co-existing amyloid pathology may affect cognitive function in people with VCI.Methods:We conducted a planned sub-analysis of a randomized controlled trial investigating the effect of targeted aerobic exercise training on cognitive function in people with VCI. Elevan participants 8 participants with VCI and 3 normal controls underwent a PiB-PET scan to estimate amyloid burden. Participants with VCI who exhibited PiB uptake 2 standard deviations above the mean of controls were considered to be PiB-positive and to haveMD.To determine the effect of co-existing amyloid pathology on cognitive function we collected the following measures: 1) ADAS-Cog; 2) EXIT-25; and 3) a) Digits Forward and Backwards Test, b) Stroop-Colour Word Test, and c) Trail Making Test (Part B-Part A). To determine the associations between PiB uptake and cognitive function we conducted correlational analysis using Pearson correlation coefficients. Results: Five (62.5%) participants with VCI were PiB-positive and 3 (37.5%) participants were PiB-negative. Increased PiB retention was significantly correlated with reduced cognitive performance in the ADAS-Cog (r1⁄40.849, p1⁄40.008) and the Trail Making Test (r1⁄40.861, p1⁄40.006). Conclusions: Neuroimaging with PiB-PET showed 62.5% of those with a clinical diagnosis of VCI have co-existing amyloid pathology. Critically, increased amyloid binding was associated with increased cognitive deficits in domains typically affected by both AD and VCI. Thus, our results suggest that those with VCI and co-existing amyloid pathology demonstrate more diverse cognitive deficits. M ore research is needed to develop reliable and valid measures for the diagnosis of MD.