Blood‐brain barrier permeability is increased in early Alzheimer’s disease and correlates with brain microstructure

Vascular dysfunction frequently accompanies Alzheimer’s disease (AD), and its suspected contributions to AD pathogenesis may be partly mediated by disrupted blood‐brain barrier (BBB) function. Despite consistent evidence for increased BBB permeability in AD, it remains unclear whether BBB damage occurs in preclinical stages, when therapeutic interventions may be most effective. Furthermore, the relationship between BBB breakdown and microstructural neurodegenerative changes have not been well characterized.