Pericyte loss in cognitive-impairment-prone hippocampal regions precedes blood-brain barrier breakdown and is detectable before clinical Alzheimer disease symptom onset; this provides a timing-window for biomarker-driven intervention.

Evidence span

Individuals with early cognitive dysfunction develop BBB breakdown in the hippocampus, irrespective of Alzheimer disease amyloid-β or tau pathway biomarker changes. Pericyte injury, indicated by elevated cerebrospinal fluid soluble PDGFRβ, is detectable before clinical onset and correlates with the BBB breakdown signature.

Method & conditions

Evidence type

observational

Method

manual state transition

Conditions

Manually added finding; requires evidence review before scientific use.

Replicated

not yet

Confidence basis

operator-supplied frontier prior; review required