Experiment challenge for hypothesis: Elevated CSF/Serum Albumin Quotient Predicts Neurodegeneration Progression Independent of Age ## Mechanistic Hypothesis Serum albumin is synthesized exclusively by the liver and absent from CNS under normal BBB. When barrier permeability increases, albumin leaks into CSF at rates proportional to disruption severity. The albumin quotient (QAlb) provides a validated, quantitative index of global BBB integrity. QAlb elevation above age-adjusted reference ranges precedes measurable cognitive decline and represents a cost-effective screening tool for prodromal neurodegeneration when combined with disease-specific biom ## Target Gene/Pathway ALB ## Disease Context Neurodegeneration ## Evidence Supporting this Hypothesis [{'pmid': '31068575', 'claim': 'Elevated QAlb predicts dementia risk independent of amyloid/tau status in cognitively unimpaired elderly'}, {'pmid': '32466612', 'claim': 'QAlb correlates with NfL and GFAP in AD, indicating barrier dysfunction tracks with neuronal injury'}, {'pmid': '33340877', 'clai ## Evidence Against / Caveats [{'pmid': '33340877', 'claim': 'QAlb elevated in multiple neurological conditions including MS, infections, stroke—not specific to neurodegeneration'}, {'pmid': '35653647', 'claim': 'QAlb highly varia ## Composite Score 0.825 (mechanistic plausibility: 0.70, feasibility: 0.70, impact: 0.70, confidence: 0.70)