2 results
17 Education Moderates the Association Between Hippocampal CBF and Memory in Women but Not Men
- Einat K Brenner, Alexandra J Weigand, Lauren C Edwards, Amanda T Calcetas, Maria Bordyug, Sarah J Banks, Erin E Sundermann, Kelsey R Thomas, Mark W Bondi, Katherine J Bangen
-
- Journal:
- Journal of the International Neuropsychological Society / Volume 29 / Issue s1 / November 2023
- Published online by Cambridge University Press:
- 21 December 2023, pp. 227-228
-
- Article
-
- You have access Access
- Export citation
-
Objective:
Higher educational attainment is associated with reduced risk for Alzheimer's disease (AD) dementia, and its protective effect may act through alterations in cerebral blood flow (CBF) that allow for better coping with accumulating neuropathology. Additionally, there are sex differences in both the risk of developing AD as well as the potential protective effects of education. We therefore sought to investigate whether education moderates the association of hippocampal CBF and memory in cognitively unimpaired older adults, and to examine if these interactions were moderated by sex.
Participants and Methods:Cognitively unimpaired older adults from the Alzheimer's Disease Neuroimaging Initiative (ADNI; 51 men, 50 women) underwent neuropsychological evaluation and arterial spin labeling MRI, which was used to quantify bilateral hippocampal CBF. Sex was defined as sex at birth. Multiple linear regressions assessed (1) the independent associations among education, CBF, and memory performance separately in men and women and (2) the three-way interactions among CBF, sex, and education, followed by sex-stratified analyses. Three outcome measures were examined: Logical Memory Story A immediate and delayed recall, and Rey Auditory Verbal Learning Test (RAVLT) intrusions. All models adjusted for age and APOE epsilon-4 allele frequency, and all models with CBF additionally adjusted for cerebral metabolism (baseline FDG-PET composite) and pulse pressure.
Results:CBF was not associated with education or memory in either women or men. There was a positive association between education and delayed memory in women (ß=0.14, t=2.64, p=0.008) as well as trending, positive associations between education and immediate memory in women (ß=0.09, t=1.79, p=0.074) and education and delayed memory in men (ß=0.09, t=1.94, p=0.054). Three-way interactions among sex, CBF, and education were significant on immediate recall (ß=2.55, t=2.53, p=0.013), delayed recall (ß=2.56, t=2.44, p=0.017), and RAVLT intrusions (ß=-2.28, t=-2.27, p=0.026). In women, there were interactions between education and hippocampal CBF on both immediate (ß=2.49, t=2.90, p=0.006) and delayed recall (ß=2.30, t=2.78, p=0.009), such that as education increased, the strength of the association between CBF and immediate memory increased. There was also an interaction between education and hippocampal CBF on RAVLT intrusions in women (ß=-2.42, t=-3.05, p=0.004), such that as education increased, the strength of the association between CBF and number of intrusions decreased; there was a main effect where in women with lower education, as CBF increased, the number of intrusions increased (ß=0.76, t=2.59, p=0.032); in women with higher education, there was no association between CBF and intrusions. In men, none of these two-way interactions were significant.
Conclusions:These results suggest that, in cognitively unimpaired older women, the relationship between hippocampal CBF and memory is moderated by education level, even when adjusting for several other factors. Specifically, higher education may serve as a protective factor in the hippocampal CBF-memory relationship, and this relationship was sex-dependent, occurring in women only. Further research is needed to examine these relationships longitudinally across the clinical continuum of AD. Additionally, this work needs to be conducted in more diverse samples to allow for analyses investigating the impact of education on the intersection of race/ethnicity and sex/gender.
Greater accelerometer-measured physical activity is associated with better cognition and cerebrovascular health in older adults
- Katherine J. Bangen, Amanda T. Calcetas, Kelsey R. Thomas, Christina Wierenga, Christine N. Smith, Maria Bordyug, Einat K. Brenner, David Wing, Conan Chen, Thomas T. Liu, Zvinka Z. Zlatar
-
- Journal:
- Journal of the International Neuropsychological Society / Volume 29 / Issue 9 / November 2023
- Published online by Cambridge University Press:
- 15 February 2023, pp. 859-869
-
- Article
-
- You have access Access
- Open access
- HTML
- Export citation
-
Objectives:
Physical activity (PA) may help maintain brain structure and function in aging. Since the intensity of PA needed to effect cognition and cerebrovascular health remains unknown, we examined associations between PA and cognition, regional white matter hyperintensities (WMH), and regional cerebral blood flow (CBF) in older adults.
Method:Forty-three older adults without cognitive impairment underwent magnetic resonance imaging (MRI) and comprehensive neuropsychological assessment. Waist-worn accelerometers objectively measured PA for approximately one week.
Results:Higher time spent in moderate to vigorous PA (MVPA) was uniquely associated with better memory and executive functioning after adjusting for all light PA. Higher MVPA was also uniquely associated with lower frontal WMH volume although the finding was no longer significant after additionally adjusting for age and accelerometer wear time. MVPA was not associated with CBF. Higher time spent in all light PA was uniquely associated with higher CBF but not with cognitive performance or WMH volume.
Conclusions:Engaging in PA may be beneficial for cerebrovascular health, and MVPA in particular may help preserve memory and executive function in otherwise cognitively healthy older adults. There may be differential effects of engaging in lighter PA and MVPA on MRI markers of cerebrovascular health although this needs to be confirmed in future studies with larger samples. Future randomized controlled trials that increase PA are needed to elucidate cause-effect associations between PA and cerebrovascular health.