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 #58 Decline in Inhibition and Attentional Control Across Early Stages of Alzheimer’s Disease Melanie Johnson, San Diego State University, San Diego, United States Kelsey Thomas, University of California, San Diego, San Diego, United States Douglas Galasko, University of California, San Diego, San Diego, United States Mark Bondi, University of California, San Diego, San Diego, United States Tamar Gollan, University of California, San Diego, San Diego, United States Diane Jacobs, University of California, San Digo, San Diego, United States Dean Delis, University of California, San Diego, San Diego, United States David Salmon, University of California, San Diego, San Diego, United States Category: Dementia (Alzheimer's Disease) Keyword 1: inhibitory control Keyword 2: attention Keyword 3: dementia - Alzheimer's disease Objective: Neuropathologic changes of Alzheimer’s disease (e.g., spreading accumulation of beta amyloid (Aβ) plaques and tau neurofibrillary tangles) begin well before the gradual emergence of obvious cognitive deficits that lead to a diagnosis of dementia. Early involvement of frontal and parietal cortical systems in the Alzheimer’s disease (AD) neuropathologic process suggest that a decline in attentional control mechanisms required to inhibit prepotent responses may be an early preclinical or prodromal marker of disease. Therefore, we assessed inhibition and attentional control and how it changes over time in early stages of AD using an expanded version of the classic Stroop test, the Delis-Kaplan Executive Function System (D-KEFS) Color Word Interference Test (CWIT). Participants and Methods: The CWIT was administered at baseline to four groups of older adults: cognitively normal CSF AD biomarker-negative (CN-; n=119), CN biomarker-positive (CN+ or preclinical AD; n=44; CSF tau/Aβ ratio>.609), mild cognitive impairment (MCI; n=19) and mild AD dementia (AD; n=15). MCI and AD were all biomarker-positive. A subsample of CN- (n=95), CN+ (n=38), and cognitively impaired (CI; 13 MCI plus 7 AD) participants completed the CWIT at two additional annual evaluations. The CWIT assesses inhibition and attentional control by contrasting time to complete four conditions: naming the color of 50 ink patches (Color Naming), reading 50 color names (Word Reading), naming the color of 50 incongruent color names (Inhibition), and 50 trials of signaled switching between naming the color of incongruent words or reading color word names (Inhibition/Switching). An interference effect was calculated as the difference between Inhibition and Color Naming completion times. Results: Analyses of covariance (ANCOVAs) controlling for age, education, and sex showed group differences at baseline for Color Naming (F[3,190]=6.50; p<.001), Inhibition (F[3,190=17.02; p<.001), Inhibition/Switching (F[3,188]=49.23; p<.001) and the interference effect (F[3,190]=15.44; p<.001). Post-hoc pairwise comparisons showed AD>MCI>CN+=CN- for Inhibition and Inhibition/Switching completion times, and AD>MCI>CN- for the interference effect (MCI=CN+ and CN+=CN-). Repeated measures ANCOVAs examining longitudinal change over two years revealed group X year interactions for Word Reading (F[4,294]=3.02; p<.05), Color Naming (F[4,294]=2.41; p<.05), Inhibition (F[3.4,248.4.]=10.85; p<.001), Inhibition/Switching (F[3.56,256.2]=3.00; p<.05), and the interference effect (F[4,292]=8.09; p<.001). Pairwise group comparisons of change scores (yr.3–yr.1) showed CI declined more than CN- on all measures and more than CN+ on Word Reading and Inhibition. Decline by CN+ and CN- did not differ in any condition. However, across all CN participants, higher total tau was associated with faster decline on the Inhibition (b=-0.003, SE=0.001, p<.05), Inhibition/Switching (b=-0.006, SE=0.002, p<.01) and interference effect (b=-0.002, SE=0.001, p<.05) measures, with stronger associations in younger participants (tau X age interactions: p=.049, p=.004 and p=.029, respectively). Conclusions: Decline in inhibition and attentional control mediated by frontal-parietal cortical systems becomes evident in the prodromal (i.e., MCI) stage of AD, but is not readily apparent in preclinical AD when early neuropathologic markers of AD can be first detected. However, high CSF tau in CN older adults predicts rate of decline in inhibition and attentional control. Predictive power may be reduced as CN individuals age due to other age-related pathology (e.g., TDP-43 or vascular pathology).

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 #58

Decline in Inhibition and Attentional Control Across Early Stages of Alzheimer’s Disease

Melanie Johnson, San Diego State University, San Diego, United States
Kelsey Thomas, University of California, San Diego, San Diego, United States
Douglas Galasko, University of California, San Diego, San Diego, United States
Mark Bondi, University of California, San Diego, San Diego, United States
Tamar Gollan, University of California, San Diego, San Diego, United States
Diane Jacobs, University of California, San Digo, San Diego, United States
Dean Delis, University of California, San Diego, San Diego, United States
David Salmon, University of California, San Diego, San Diego, United States

Category: Dementia (Alzheimer's Disease)

Keyword 1: inhibitory control
Keyword 2: attention
Keyword 3: dementia - Alzheimer's disease

Objective:

Neuropathologic changes of Alzheimer’s disease (e.g., spreading accumulation of beta amyloid (Aβ) plaques and tau neurofibrillary tangles) begin well before the gradual emergence of obvious cognitive deficits that lead to a diagnosis of dementia. Early involvement of frontal and parietal cortical systems in the Alzheimer’s disease (AD) neuropathologic process suggest that a decline in attentional control mechanisms required to inhibit prepotent responses may be an early preclinical or prodromal marker of disease. Therefore, we assessed inhibition and attentional control and how it changes over time in early stages of AD using an expanded version of the classic Stroop test, the Delis-Kaplan Executive Function System (D-KEFS) Color Word Interference Test (CWIT).

Participants and Methods:

The CWIT was administered at baseline to four groups of older adults: cognitively normal CSF AD biomarker-negative (CN-; n=119), CN biomarker-positive (CN+ or preclinical AD; n=44; CSF tau/Aβ ratio>.609), mild cognitive impairment (MCI; n=19) and mild AD dementia (AD; n=15). MCI and AD were all biomarker-positive. A subsample of CN- (n=95), CN+ (n=38), and cognitively impaired (CI; 13 MCI plus 7 AD) participants completed the CWIT at two additional annual evaluations. The CWIT assesses inhibition and attentional control by contrasting time to complete four conditions: naming the color of 50 ink patches (Color Naming), reading 50 color names (Word Reading), naming the color of 50 incongruent color names (Inhibition), and 50 trials of signaled switching between naming the color of incongruent words or reading color word names (Inhibition/Switching). An interference effect was calculated as the difference between Inhibition and Color Naming completion times.

Results:

Analyses of covariance (ANCOVAs) controlling for age, education, and sex showed group differences at baseline for Color Naming (F[3,190]=6.50; p<.001), Inhibition (F[3,190=17.02; p<.001), Inhibition/Switching (F[3,188]=49.23; p<.001) and the interference effect (F[3,190]=15.44; p<.001). Post-hoc pairwise comparisons showed AD>MCI>CN+=CN- for Inhibition and Inhibition/Switching completion times, and AD>MCI>CN- for the interference effect (MCI=CN+ and CN+=CN-). Repeated measures ANCOVAs examining longitudinal change over two years revealed group X year interactions for Word Reading (F[4,294]=3.02; p<.05), Color Naming (F[4,294]=2.41; p<.05), Inhibition (F[3.4,248.4.]=10.85; p<.001), Inhibition/Switching (F[3.56,256.2]=3.00; p<.05), and the interference effect (F[4,292]=8.09; p<.001). Pairwise group comparisons of change scores (yr.3–yr.1) showed CI declined more than CN- on all measures and more than CN+ on Word Reading and Inhibition. Decline by CN+ and CN- did not differ in any condition. However, across all CN participants, higher total tau was associated with faster decline on the Inhibition (b=-0.003, SE=0.001, p<.05), Inhibition/Switching (b=-0.006, SE=0.002, p<.01) and interference effect (b=-0.002, SE=0.001, p<.05) measures, with stronger associations in younger participants (tau X age interactions: p=.049, p=.004 and p=.029, respectively).

Conclusions:

Decline in inhibition and attentional control mediated by frontal-parietal cortical systems becomes evident in the prodromal (i.e., MCI) stage of AD, but is not readily apparent in preclinical AD when early neuropathologic markers of AD can be first detected. However, high CSF tau in CN older adults predicts rate of decline in inhibition and attentional control. Predictive power may be reduced as CN individuals age due to other age-related pathology (e.g., TDP-43 or vascular pathology).