NIH Toolbox Cognitive Battery in non-Hispanic Black individuals: role of cerebral vascular function, pulse wave velocity, and psychosocial stress exposure
Authors: Kolade John , Ortiz Alison , Abdelsaid Abanoub , Brothers Robert 
Published: May 2023

Non-Hispanic Black (BL) individuals are ~ 2 times more likely to develop cognitive impairment, Alzheimer’s disease, and related dementias (ADRD) relative to other populations. ADRD prevalence is expected to double by 2060, with a greater increase in BL and Hispanic populations. Reduced cerebral vascular function and large elastic artery health increases risk for cognitive decline and ADRD. In addition, psychosocial stress exposure, including at a young age, is a significant predictor of intellectual function and executive attention. However, the relationship between 1) cerebral & peripheral vascular function/health and indices of cognitive function, and 2) psychosocial stress exposure and indices of cognitive function in relatively young, healthy BL individuals are incompletely understood. We tested the hypothesis that cerebral vascular function and large elastic artery health are blunted in BL individuals, which will be associated with reduced cognitive performance. We also hypothesized that psychosocial stress exposure in the BL individuals is negatively associated with cognitive performance. METHODS: Eight BL (2 males; age: 20±1 yr; BMI: 22±3 kg/m2) and 8 WH (4 males; age: 20±3 yr; BMI: 23±2 kg/m2) individuals participated. Cognitive function was indexed using the NIH Toolbox Cognitive Battery which compiles a fluid score (i.e., capacity for new learning and information processing in novel situations), a crystallized score (i.e., past learning experiences), and a total cognition score. Cerebral vascular function was assessed as the % increase in cerebral vascular conductance (CVCi = middle cerebral artery blood velocity/mean arterial pressure) during hypercapnia (6% CO2). Large elastic artery health was assessed as aortic pulse wave velocity (PWV). Psychosocial stress exposure was assessed as adverse childhood experiences (ACEs). RESULTS: The national percentile and age-adjusted fluid and total scores were lower in the BL individuals ( P<0.05 for each), whereas the crystallized score was not different ( P=0.79). The % increase in CVCi during hypercapnia (BL: 32±15, WH: 54±50%, P=0.26) and PWV (BL: 5.7±0.9, WH: 5.7±0.9 m·s-1, P=0.96) was similar between groups. Within the BL individuals there was not a significant correlation between %CVCi or PWV and the fluid, crystallized, or total scores ( P>0.05 for each) while ACEs tended to be negatively associated with total ( P=0.06) but not fluid or crystallized scores ( P>0.05 for each). CONCLUSION: These preliminary data suggest that young, healthy BL individuals may have reduced indices of cognitive function, particularly in the fluid domain, which may be associated with ACEs. This does not appear to be related to cerebral vascular function or large elastic artery stiffness. Future work will continue to assess these relationships in a population with a wider age range and more diverse life experiences. NIH R15 (HL156128, RMB) & Peanut Institute (982307, RMB) This is the full abstract presented at the American Physiology Summit 2023 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.