Grip strength modifies the association between blood-based alzheimer’s biomarkers and cognitive function

(β = - 0.046, p < 0.01), NfL (β = - 0.002, p < 0.001), and GFAP (β = - 0.005, p < 0.05). Age-matched showed attenuation of some interaction effects except for low grip strength and NfL. Age-stratified analyses showed a significant interaction for NfL among adults ≥ 65 years and for GFAP among those < 65 years. Grip strength moderated the association between plasma AD-related biomarkers and cognitive performance, supporting physical strength as an indicator of vulnerability. Integrating simple strength measures with blood biomarkers may improve cognitive risk stratification in community-dwelling adults.