INS NYC 2024 Program

Poster	Poster Session 06 Program Schedule 02/15/2024 04:00 pm - 05:15 pm Room: Shubert Complex (Posters 1-60) Poster Session 06: Aging \| MCI \| Neurodegenerative Disease - PART 2 Final Abstract #38 Short-term Practice Effects on Cognitive Tests Across the Late Life Cognitive Spectrum and how they Compare to Biomarkers of Alzheimer’s Disease Kevin Duff, Oregon Health & Science University, Portland, United States Dustin Hammers, Indiana University School of Medicine, Indianapolis, United States Vincent Koppelmans, University of Utah, Salt Lake City, United States Jace King, University of Utah, Salt Lake City, United States John Hoffman, University of Utah, Salt Lake City, United States Category: Dementia (Alzheimer's Disease) Keyword 1: cognitive course Keyword 2: neuroimaging: structural Keyword 3: test reliability Objective: Although practice effects on cognitive testing in Mild Cognitive Impairment (MCI) and Alzheimer’s disease (AD) have been examined, most studies have considered practice effects across long periods of time (e.g., months to years) and few have examined how practice effects compare to other biomarkers of AD. The current study sought to examine short-term practice effects for multiple cognitive domains across one week in cognitively healthy older adults, as well as those with MCI and mild AD, and then compare practice effects to three common biomarkers in AD: amyloid deposition, hippocampal volume, and APOE e4 alleles. Participants and Methods: Cognitively intact older adults (n=69), those with amnestic MCI (n=52), and those with mild AD (n=45) were given the same brief battery of cognitive tests twice across one week, and practice effects were quantified using regression-based change scores. These participants also completed a baseline MRI to obtain hippocampal volumes, a baseline amyloid PET scan to obtain amyloid deposition, and a baseline blood draw to obtain APOE e4 status. Results: After controlling for age differences between the groups, the intact participants showed significantly larger practice effects than the other two groups on a composite measure and all seven individual cognitive scores. The MCI showed significantly larger practice effects than the AD participants on the composite and 5 of the 7 individual cognitive scores. For amyloid deposition, the intact participants had significantly less tracer uptake on a global composite score, whereas the MCI and AD participants were comparable. For right and left hippocampal volumes, all three groups were significantly different in the expected direction (intact>MCI>AD). For APOE e4, the intact participants had significant fewer copies of e4, but the MCI and AD participants were comparable. When examining effect sizes of group differences (e.g., intact vs. MCI), practice effects across one week on tests of learning and memory were larger than practice effects on tests of processing speed. Furthermore, the effect sizes for practice effects on tests of learning and memory were larger than effect sizes based on biomarkers. Conclusions: Short-term practice effects, like those measured across one week, appear to be a particularly sensitive marker in late life cognitive disorders. Across this late life spectrum, short-term practice effects on tests of learning and memory appear more sensitive than practice effects on processing speed tests. These practice effects also separate the groups better than commonly-used biomarkers in AD. Future refinement of short-term practice effects as a tool for clinical diagnosis, prognostic indication, and enrichment of clinical trials seems warranted.

Poster

02/15/2024
04:00 pm - 05:15 pm
Room: Shubert Complex (Posters 1-60)

Poster Session 06: Aging | MCI | Neurodegenerative Disease - PART 2

Final Abstract #38

Short-term Practice Effects on Cognitive Tests Across the Late Life Cognitive Spectrum and how they Compare to Biomarkers of Alzheimer’s Disease

Kevin Duff, Oregon Health & Science University, Portland, United States
Dustin Hammers, Indiana University School of Medicine, Indianapolis, United States
Vincent Koppelmans, University of Utah, Salt Lake City, United States
Jace King, University of Utah, Salt Lake City, United States
John Hoffman, University of Utah, Salt Lake City, United States

Category: Dementia (Alzheimer's Disease)

Keyword 1: cognitive course
Keyword 2: neuroimaging: structural
Keyword 3: test reliability

Objective:

Although practice effects on cognitive testing in Mild Cognitive Impairment (MCI) and Alzheimer’s disease (AD) have been examined, most studies have considered practice effects across long periods of time (e.g., months to years) and few have examined how practice effects compare to other biomarkers of AD. The current study sought to examine short-term practice effects for multiple cognitive domains across one week in cognitively healthy older adults, as well as those with MCI and mild AD, and then compare practice effects to three common biomarkers in AD: amyloid deposition, hippocampal volume, and APOE e4 alleles.

Participants and Methods:

Cognitively intact older adults (n=69), those with amnestic MCI (n=52), and those with mild AD (n=45) were given the same brief battery of cognitive tests twice across one week, and practice effects were quantified using regression-based change scores. These participants also completed a baseline MRI to obtain hippocampal volumes, a baseline amyloid PET scan to obtain amyloid deposition, and a baseline blood draw to obtain APOE e4 status.

Results:

After controlling for age differences between the groups, the intact participants showed significantly larger practice effects than the other two groups on a composite measure and all seven individual cognitive scores. The MCI showed significantly larger practice effects than the AD participants on the composite and 5 of the 7 individual cognitive scores. For amyloid deposition, the intact participants had significantly less tracer uptake on a global composite score, whereas the MCI and AD participants were comparable. For right and left hippocampal volumes, all three groups were significantly different in the expected direction (intact>MCI>AD). For APOE e4, the intact participants had significant fewer copies of e4, but the MCI and AD participants were comparable. When examining effect sizes of group differences (e.g., intact vs. MCI), practice effects across one week on tests of learning and memory were larger than practice effects on tests of processing speed. Furthermore, the effect sizes for practice effects on tests of learning and memory were larger than effect sizes based on biomarkers.

Conclusions:

Short-term practice effects, like those measured across one week, appear to be a particularly sensitive marker in late life cognitive disorders. Across this late life spectrum, short-term practice effects on tests of learning and memory appear more sensitive than practice effects on processing speed tests. These practice effects also separate the groups better than commonly-used biomarkers in AD. Future refinement of short-term practice effects as a tool for clinical diagnosis, prognostic indication, and enrichment of clinical trials seems warranted.