Regional differences in the link between water exchange rate across the blood –brain barrier and cognitive performance in normal aging

AbstractThe blood –brain barrier (BBB) undergoes functional changes with aging which may contribute to cognitive decline. A novel, diffusion prepared arterial spin labeling-based MRI technique can measure the rate of water exchange across the BBB (kw) and may thus be sensitive to age-related alterations in water exchange at the BBB. However, studies investigating relationships betweenkw and cognition have reported different directions of association. Here, we begin to investigate the direction of associations betweenkw and cognition in different brain regions, and their possible underpinnings, by evaluating links betweenkw, cognitive performance, and MRI markers of cerebrovascular dysfunction and/or damage. Forty-seven healthy older adults (age range 61 –84) underwent neuroimaging to obtain whole-brain measures ofkw, cerebrovascular reactivity (CVR), and white matter hyperintensity (WMH) volumes. Additionally, participants completed uniform data set (Version 3) neuropsychological tests of executive function (EF) and episodic memory (MEM). Voxel-wise linear regressions were conducted to test associations betweenkw and cognitive performance, CVR, and WMH volumes. We found thatkw in the frontoparietal brain regions was positively associated with cognitive performance but not with CVR or WMH volumes. Conversely,kw in the basal ganglia was negatively associated with cognitive performance and CVR and positively associated with regional, periventricular WMH volume. These regiona...

Source: AGE - September 15, 2023 Category: Geriatrics Source Type: research