INS NYC 2024 Program

Poster	Poster Session 06 Program Schedule 02/15/2024 04:00 pm - 05:15 pm Room: Majestic Complex (Posters 61-120) Poster Session 06: Aging \| MCI \| Neurodegenerative Disease - PART 2 Final Abstract #83 Cerebral Blood Flow is Associated with Memory in Older Adults with the APOE ε4 Allele Jeffrey Pyne, Columbia University, New York, United States Clarissa Morales, Columbia University, New York, United States Mohamad Alshikho, Columbia University, New York, United States Patrick Lao, Columbia University, New York, United States Indira Turney, Columbia University, New York, United States Jose Gutierrez, Columbia University, New York, United States Jennifer Manly, Columbia University, New York, United States Richard Mayeux, Columbia University, New York, United States Adam Brickman, Columbia University, New York, United States Category: Dementia (Alzheimer's Disease) Keyword 1: apolipoprotein E Keyword 2: cerebral blood flow Keyword 3: dementia - Alzheimer's disease Objective: Decreased cerebral blood flow contributes to the risk, progression, and possibly, pathogenesis of Alzheimer’s disease (AD). The APOE ε4 allele is the strongest known genetic risk factor for late onset AD. We used a novel magnetic resonance imaging (MRI)-based method, termed phase contrast, to quantitate proximal cerebral blood flow in anterior and posterior circulations and test its relationship with memory in community-dwelling older adults. We further tested whether this relationship differed between people with and without an APOE ε4 allele. Participants and Methods: Seventy-three older adult participants (78/5.4 mean/SD years old, 59% women, 34% Latinx, 29% Black, and 36% White individuals) in the Washington Heights Inwood Columbia Aging Project (WHICAP) received a neuropsychological battery, phase contrast MRI, and genetic testing for APOE status. A summary memory score was calculated based on a factor analysis of the neuropsychological battery. Two-dimensional phase contrast imaging quantified absolute blood flow rates with cross-sectional velocity-encoding of major vasculature leading into the brain. Blood flow rates in the major cerebral vasculature, anterior circulation (carotid arteries) and posterior circulation (vertebral arteries), were derived with Medis Suite QFlow 4.0. General linear models tested the association of flow variables (total, anterior, and posterior cerebral blood flow [mL/min]) and APOE ε4 allele and their interaction with memory in age and education adjusted models. Post hoc analyses stratified the sample by APOE ε4 allele to assess these relationships separately in those with higher and lower genetic risk. Results: Twenty-two percent of participants had at least one copy of the APOE ε4 allele. Interactions between APOE status and blood flow demonstrated that lower proximal total (standardized β_interaction_total = 1.71, p < 0.05, 95% CI [0.41, 3.00]) and anterior (β_interaction_anterior = 1.69, p < 0.005, CI [0.54, 2.84]) cerebral blood flow was more strongly associated with lower memory scores in APOE ε4 carriers than in APOE ε4 non-carriers. Indeed, in stratified analyses, lower proximal total (β _total = 0.64, CI [-3.3E-3, 1.29]) and anterior (β_anterior = 0.66, CI [8.5E-2, 1.24]) cerebral blood flow was associated with lower memory scores in APOE ε4 carriers, but not in APOE ε4 non-carriers (β_total = -0.06, CI [-0.29, 0.17], β_anterior = -0.09, CI [-0.32, 0.14]). There were no main effects of total (β_total = 0.32, CI [0.02, 0.62]) or anterior (β_anterior = 0.28, CI [0.03, 0.54]) blood flow on memory scores. However, individuals with APOE ε4 had lower memory scores than those without (main effect of APOE ε4, β = -0.03, p < 0.05, CI [-0.23, 0.17]). There were no main effects of posterior cerebral blood flow (β = 0.10, CI [-0.32, 0.51]), APOE status (β = -0.04, CI [-0.25, 0.17]), or their interaction (β_interaction_posterior = 0.24, CI [-0.84, 1.32]) on memory scores. Conclusions: Lower proximal total and anterior blood flow may be one driver of lower memory in APOE ε4 carriers, suggesting that one way in which APOE ε4 increases risk for AD is by moderating the impact of blood flow on cognition.

Poster

02/15/2024
04:00 pm - 05:15 pm
Room: Majestic Complex (Posters 61-120)

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

Final Abstract #83

Cerebral Blood Flow is Associated with Memory in Older Adults with the APOE ε4 Allele

Jeffrey Pyne, Columbia University, New York, United States
Clarissa Morales, Columbia University, New York, United States
Mohamad Alshikho, Columbia University, New York, United States
Patrick Lao, Columbia University, New York, United States
Indira Turney, Columbia University, New York, United States
Jose Gutierrez, Columbia University, New York, United States
Jennifer Manly, Columbia University, New York, United States
Richard Mayeux, Columbia University, New York, United States
Adam Brickman, Columbia University, New York, United States

Category: Dementia (Alzheimer's Disease)

Keyword 1: apolipoprotein E
Keyword 2: cerebral blood flow
Keyword 3: dementia - Alzheimer's disease

Objective:

Decreased cerebral blood flow contributes to the risk, progression, and possibly, pathogenesis of Alzheimer’s disease (AD). The APOE ε4 allele is the strongest known genetic risk factor for late onset AD. We used a novel magnetic resonance imaging (MRI)-based method, termed phase contrast, to quantitate proximal cerebral blood flow in anterior and posterior circulations and test its relationship with memory in community-dwelling older adults. We further tested whether this relationship differed between people with and without an APOE ε4 allele.

Participants and Methods:

Seventy-three older adult participants (78/5.4 mean/SD years old, 59% women, 34% Latinx, 29% Black, and 36% White individuals) in the Washington Heights Inwood Columbia Aging Project (WHICAP) received a neuropsychological battery, phase contrast MRI, and genetic testing for APOE status. A summary memory score was calculated based on a factor analysis of the neuropsychological battery. Two-dimensional phase contrast imaging quantified absolute blood flow rates with cross-sectional velocity-encoding of major vasculature leading into the brain. Blood flow rates in the major cerebral vasculature, anterior circulation (carotid arteries) and posterior circulation (vertebral arteries), were derived with Medis Suite QFlow 4.0. General linear models tested the association of flow variables (total, anterior, and posterior cerebral blood flow [mL/min]) and APOE ε4 allele and their interaction with memory in age and education adjusted models. Post hoc analyses stratified the sample by APOE ε4 allele to assess these relationships separately in those with higher and lower genetic risk.

Results:

Twenty-two percent of participants had at least one copy of the APOE ε4 allele. Interactions between APOE status and blood flow demonstrated that lower proximal total (standardized β_interaction_total = 1.71, p < 0.05, 95% CI [0.41, 3.00]) and anterior (β_interaction_anterior = 1.69, p < 0.005, CI [0.54, 2.84]) cerebral blood flow was more strongly associated with lower memory scores in APOE ε4 carriers than in APOE ε4 non-carriers. Indeed, in stratified analyses, lower proximal total (β _total = 0.64, CI [-3.3E-3, 1.29]) and anterior (β_anterior = 0.66, CI [8.5E-2, 1.24]) cerebral blood flow was associated with lower memory scores in APOE ε4 carriers, but not in APOE ε4 non-carriers (β_total = -0.06, CI [-0.29, 0.17], β_anterior = -0.09, CI [-0.32, 0.14]). There were no main effects of total (β_total = 0.32, CI [0.02, 0.62]) or anterior (β_anterior = 0.28, CI [0.03, 0.54]) blood flow on memory scores. However, individuals with APOE ε4 had lower memory scores than those without (main effect of APOE ε4, β = -0.03, p < 0.05, CI [-0.23, 0.17]). There were no main effects of posterior cerebral blood flow (β = 0.10, CI [-0.32, 0.51]), APOE status (β = -0.04, CI [-0.25, 0.17]), or their interaction (β_interaction_posterior = 0.24, CI [-0.84, 1.32]) on memory scores.

Conclusions:

Lower proximal total and anterior blood flow may be one driver of lower memory in APOE ε4 carriers, suggesting that one way in which APOE ε4 increases risk for AD is by moderating the impact of blood flow on cognition.