INS NYC 2024 Program

Poster	Poster Session 02 Program Schedule 02/15/2024 08:00 am - 09:15 am Room: Shubert Complex (Posters 1-60) Poster Session 02: Aging \| MCI \| Neurodegenerative Disease - PART 1 Final Abstract #9 Intraindividual Cognitive Variability is Associated with Cross-sectional and Longitudinal Tau Burden Maria Bordyug, University of California San Diego, La Jolla, United States Alexandra Weigand, SDSU/UCSD Joint Doctoral Program, San Diego, United States Lauren Edwards, SDSU/UCSD Joint Doctoral Program in Clinical Psychology, San Diego, United States Amanda Calcetas, University of California San Diego, La Jolla, United States Mark Bondi, VA San Diego Healthcare System/University of California San Diego, SAN DIEGO, United States Kelsey Thomas, VA San Diego Healthcare System/University of California, San Diego, La Jolla, United States Katherine Bangen, VA San Diego Healthcare System/University of California San Diego, San Diego, United States Category: Dementia (Alzheimer's Disease) Keyword 1: positron emission tomography Keyword 2: cognitive functioning Keyword 3: aging disorders Objective: Intraindividual cognitive variability (IIV), a measure of within person variability across cognitive measures at a single time point, is associated with cognitive decline and dementia, including Alzheimer’s disease (AD). Despite emerging evidence supporting the potential utility of IIV metrics to predict future cognitive decline, few studies have examined associations of IIV and AD biomarkers, such as amyloid and tau. Therefore, we examined cross-sectional and longitudinal associations of IIV with amyloid and tau positive emission tomography (PET) imaging. Participants and Methods: This study included 640 participants (mean age = 73.3 years, mean education = 16.5 years, female = 53.3%) from the Alzheimer’s Disease Neuroimaging Initiative. Potential participants were excluded for clinical dementia diagnosis at baseline or missing data. IIV was calculated as the intraindividual standard deviation of six age-, education-, and sex- adjusted neuropsychological z-scores including measures of language, executive functioning, and episodic memory: 1) Animal Fluency total, 2) 30-item Boston Naming Test total, 3) Trail Making Test (TMT), Part A - time to complete, 4) TMT, Part B - time to complete, 5) Rey Auditory Verbal Learning Test (AVLT) 30-min delay free recall - number of correct words, 6) AVLT recognition – number of correct words. Amyloid and tau were measured using PET imaging with a cortical composite measure of amyloid and a meta-temporal measure of tau. Linear regression was used to examine the cross-sectional association between baseline IIV and AD PET measures, adjusting for age, education, sex, mean cognitive performance, white matter hyperintensity volume, and either amyloid or tau PET (whichever was not the dependent variable for that model). Linear mixed effects models additionally examined the association between IIV and rate of change in AD PET measures across a 3-year period adjusting for the same covariates. Results: Model estimates indicated that higher IIV was significantly associated with higher tau levels at baseline even after adjusting for amyloid PET and mean cognitive performance (B=.15, t=3.68, p<.001). Additionally, higher IIV was also associated with faster increases in tau levels longitudinally across a 3-year period while adjusting for the same factors (B=.004, t=5.50, p<.001). In contrast, the association of IIV with baseline amyloid and amyloid over time was not significant (ps>.05). Conclusions: These findings suggest that higher IIV could be an important predictor of tau accumulation both at a single time point and over time. However, IIV did not relate to cross-sectional or longitudinal amyloid levels. These findings are consistent with previous research demonstrating that tau is more strongly associated with cognitive performance than amyloid, and additionally adds to the IIV literature by further highlighting the added utility of this marker in predicting dementia risk above and beyond mean level cognitive performance. These results suggest that IIV, a non-invasive and scalable marker, could be a useful predictor of AD biomarker change.

Poster

02/15/2024
08:00 am - 09:15 am
Room: Shubert Complex (Posters 1-60)

Poster Session 02: Aging | MCI | Neurodegenerative Disease - PART 1

Final Abstract #9

Intraindividual Cognitive Variability is Associated with Cross-sectional and Longitudinal Tau Burden

Maria Bordyug, University of California San Diego, La Jolla, United States
Alexandra Weigand, SDSU/UCSD Joint Doctoral Program, San Diego, United States
Lauren Edwards, SDSU/UCSD Joint Doctoral Program in Clinical Psychology, San Diego, United States
Amanda Calcetas, University of California San Diego, La Jolla, United States
Mark Bondi, VA San Diego Healthcare System/University of California San Diego, SAN DIEGO, United States
Kelsey Thomas, VA San Diego Healthcare System/University of California, San Diego, La Jolla, United States
Katherine Bangen, VA San Diego Healthcare System/University of California San Diego, San Diego, United States

Category: Dementia (Alzheimer's Disease)

Keyword 1: positron emission tomography
Keyword 2: cognitive functioning
Keyword 3: aging disorders

Objective:

Intraindividual cognitive variability (IIV), a measure of within person variability across cognitive measures at a single time point, is associated with cognitive decline and dementia, including Alzheimer’s disease (AD). Despite emerging evidence supporting the potential utility of IIV metrics to predict future cognitive decline, few studies have examined associations of IIV and AD biomarkers, such as amyloid and tau. Therefore, we examined cross-sectional and longitudinal associations of IIV with amyloid and tau positive emission tomography (PET) imaging.

Participants and Methods:

This study included 640 participants (mean age = 73.3 years, mean education = 16.5 years, female = 53.3%) from the Alzheimer’s Disease Neuroimaging Initiative. Potential participants were excluded for clinical dementia diagnosis at baseline or missing data. IIV was calculated as the intraindividual standard deviation of six age-, education-, and sex- adjusted neuropsychological z-scores including measures of language, executive functioning, and episodic memory: 1) Animal Fluency total, 2) 30-item Boston Naming Test total, 3) Trail Making Test (TMT), Part A - time to complete, 4) TMT, Part B - time to complete, 5) Rey Auditory Verbal Learning Test (AVLT) 30-min delay free recall - number of correct words, 6) AVLT recognition – number of correct words. Amyloid and tau were measured using PET imaging with a cortical composite measure of amyloid and a meta-temporal measure of tau. Linear regression was used to examine the cross-sectional association between baseline IIV and AD PET measures, adjusting for age, education, sex, mean cognitive performance, white matter hyperintensity volume, and either amyloid or tau PET (whichever was not the dependent variable for that model). Linear mixed effects models additionally examined the association between IIV and rate of change in AD PET measures across a 3-year period adjusting for the same covariates.

Results:

Model estimates indicated that higher IIV was significantly associated with higher tau levels at baseline even after adjusting for amyloid PET and mean cognitive performance (B=.15, t=3.68, p<.001). Additionally, higher IIV was also associated with faster increases in tau levels longitudinally across a 3-year period while adjusting for the same factors (B=.004, t=5.50, p<.001). In contrast, the association of IIV with baseline amyloid and amyloid over time was not significant (ps>.05).

Conclusions:

These findings suggest that higher IIV could be an important predictor of tau accumulation both at a single time point and over time. However, IIV did not relate to cross-sectional or longitudinal amyloid levels. These findings are consistent with previous research demonstrating that tau is more strongly associated with cognitive performance than amyloid, and additionally adds to the IIV literature by further highlighting the added utility of this marker in predicting dementia risk above and beyond mean level cognitive performance. These results suggest that IIV, a non-invasive and scalable marker, could be a useful predictor of AD biomarker change.