Cerebral vascular function in young, healthy non-Hispanic Black and White females
Authors: Ortiz Alison , Martin Zachary , Kolade John , Al-daas Iman , Cardenas Natalia , Merlau Emily , Vu Joshua , Brown Kyrah , Brothers R. 
Published: May 2023

Non-Hispanic Black (BL) individuals are ~2-times more likely to suffer from conditions including cognitive dysfunction and Alzheimer’s disease and related dementias (ADRD) – conditions which are among the fastest growing causes of morbidity and mortality in the US. The prevalence of ADRD is expected to double by 2060 with a more rapid increase in the BL (and Hispanic) population. Importantly, reduced vascular function, particularly in the cerebral circulation, contributes to elevated risk for and prevalence of ADRD. While previous research has provided valuable insight into mechanisms of cerebral vascular dysfunction, this work has been primarily conducted in males and has largely not included socioeconomic/racial discrimination measurements, which are critical to understanding race/ethnicity-related disparities in cerebral vascular health. To our knowledge no studies have specifically examined cerebral vascular function in young, healthy BL females relative to WH females. Therefore, we tested the hypothesis that cerebral vascular function would be blunted in BL relative to WH females. METHODS: Eleven healthy WH (age: 26±7 yr; BMI: 26±3 kg/m2) and 17 healthy (age: 21±2 yr; BMI: 26±4 kg/m2) BL females participated. Beat-to-beat blood pressure, end-tidal carbon dioxide tension, and middle cerebral artery mean blood velocity (MCAVmean) were continuously collected. Transfer function analysis (i.e. gain, phase, and coherence) of blood pressure and MCAVmean were calculated in the very-low, low, and high-frequency ranges to assess cerebral autoregulation. Cerebral vascular function was also assessed as the % increase in MCA vascular conductance (CVCi = MCAVmean/mean arterial pressure) during administration of a hypercapnic gas (6% CO2 gas). Socioeconomic background and psychosocial stress exposures were assessed as: 1) parental education level; 2) adverse childhood experiences (ACEs); and 3) perceived ethnic discrimination (PEDQ). RESULTS: Transfer function analysis of gain, phase, and coherence was similar across all frequency ranges ( P>0.05 for all) and the % increase in CVCi ( P=0.71) during hypercapnia was similar between BL and WH females. Although perceived ethnic discrimination was greater in BL relative to WH females ( P<0.001), there were no group differences in parental education level nor ACEs ( P>0.05 for both). CONCLUSION: These preliminary data suggest that cerebral vascular function is not different between young, healthy BL and WH females of similar socioeconomic background. Future studies should continue to examine these relationships but expand inclusion to a wider age group with a greater diversity in socioeconomic background. Funding: NIH R15 (HL156128, RMB) & AHA Predoctoral Fellowship (915133, ZTM) 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.