To determine which plasma biomarker best predicts cognitive decline, this study compared baseline concentrations of tTau, pTau181, Aβ42, Aβ40, NFL, and GFAP, as well as their composite ratios Aβ42/Aβ40, pTau181/Aβ42, and pTau181/tTau, with cognitive scores. Here, NEFL is linked to Mental deterioration.