Impaired perfusion and capillary dysfunction in prodromal Alzheimer's disease.

ABSTRACT: Introduction:Cardiovascular disease increases the risk of developing Alzheimer's disease (AD), and growing evidence suggests an involvement of cerebrovascular pathology in AD. Capillary dysfunction, a condition in which capillary flow disturbances rather than arterial blood supply limit brain oxygen extraction, could represent an overlooked vascular contributor to neurodegeneration. We examined whether cortical capillary transit-time heterogeneity (CTH), an index of capillary dysfunction, is elevated in amyloid-positive patients with mild cognitive impairment (prodromal AD [pAD]). Methods:We performed structural and perfusion weighted MRI in 22 pAD patients and 21 healthy controls. Results:We found hypoperfusion, reduced blood volume, and elevated CTH in the parietal and frontal cortices of pAD-patients compared to controls, while only the precuneus showed focal cortical atrophy. Discussion:We propose that microvascular flow disturbances antedate cortical atrophy and may limit local tissue oxygenation in pAD. We speculate that capillary dysfunction contributes to the development of neurodegeneration in AD.

SUBMITTER: Nielsen RB 

PROVIDER: S-EPMC7241262 | biostudies-literature | 2020

REPOSITORIES: biostudies-literature