GFAP and Alzheimer disease: <h4>Background</h4>Plasma glial fibrillary acidic protein (GFAP), neurofilament light (NfL), phosphorylated tau217 (p-tau217), and the β-amyloid (Aβ) 42/40 ratio are emerging indicators of neuroinflammation, neurodegeneration, and AD-specific pathology, while their specific roles within Alzheimer's disease (AD) and cerebral small vessel disease (CSVD) comorbidity are not fully understood.<h4>Methods</h4>Participants with normal cognition or mild cognitive impairment were drawn from the Alzheimer's Disease Neuroimaging Initiative database.