CSF Albumin Quotient as a Marker of Blood–Brain Barrier Dysfunction in Cerebral Amyloid Angiopathy

This study examines blood–brain barrier (BBB) integrity in cerebral amyloid angiopathy using the CSF/serum albumin quotient (Qalb) as a fluid biomarker. Qalb levels are compared between patients with CAA, Alzheimer’s disease, and controls, and their diagnostic performance is evaluated. Within CAA, associations between elevated Qalb and MRI markers of disease severity are analyzed to clarify the role of BBB dysfunction and vascular inflammation in CAA pathophysiology.