Cerebrovascular reactivity in hypertensive older adults: a resting-state BOLD fMRI study

Motivation: Aging causes profound changes to the brain vasculature, but the effect of pathologies like hypertension on the aging brain is unknown. Goal(s): We sought to understand the effect of hypertension on cerebrovascular reactivity (CVR) in older adults and its association with other clinical parameters. Approach: We used resting state fMRI to calculate CVR in 41 hypertensive participants and 31 normotensive controls. Results: The hypertensive group had lower CVR in the anterior cingulate cortex (ACC) compared to the normotensive group. Higher serum high-density lipoprotein (HDL) cholesterol levels were positively correlated to ACC CVR in the normotensive group but not the hypertensive group. Impact: Hypertension compounds the effect of aging on the brain's vasculature and increases endothelial dysfunction. Notably, we observed the novel result that high-density lipoprotein (HDL) cholesterol levels to be protective of endothelial function in the absence of hypertension.