CP and Alzheimer disease: A new imaging investigation in a cross-sectional analysis (N = 216) from Ruijin NeuroBank of Alzheimer’s Disease and Dementia (RJNB-D) cohort showed that the increased CP free water fraction (FWf; indicator of the barrier and structural degeneration), had a positive correlation with increased NfL levels, suggesting that CP dysfunction might increase axonal damage or inhibit NfL clearance in the neurodegeneration [76].