Enlarged Perivascular Spaces and Plasma Aβ42/Aβ40 Ratio in Older Adults Without Dementia

Dilation of perivascular spaces (PVS) in the brain may indicate poor fluid drainage due to the accumulation of perivascular cell debris, waste, and proteins, including amyloid-beta (A beta). No prior study has assessed whether plasma A beta levels are related to PVS in older adults without dementia. Independently living older adults (N = 56, mean age = 68.2 years; Standard deviation (SD) = 6.5; 30.4% male) free of dementia or clinical stroke were recruited from the community and underwent brain MRI and venipuncture. PVS were qualitatively scored and dichotomized to low PVS burden (scores 0-1,) or high PVS burden (score > 1). Plasma was assayed using a Quanterix Simoa Kit to quantify A beta 42 and A beta 40 levels. A significant difference was observed in plasma A beta 42/A beta 40 ratio between low and high PVS burden, controlling for age (F[1, 53] = 5.59, p = 0.022, eta(2) = 0.10), with lower A beta 42/A beta 40 ratio in the high PVS burden group. Dilation of PVS is associated with a lower plasma A beta 42/A beta 40 ratio, which may indicate higher cortical amyloid deposition. Future longitudinal studies examining PVS changes, and the pathogenesis of AD are warranted. (c) 2023 The Authors. Published by Elsevier Inc. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).