GFAP and Alzheimer disease: Generalized Estimating Equations (GEE) models were used to evaluate the association between baseline nutrient intake tertile and changes in biomarkers including phospho-tau181, amyloid-beta 42/40 ratio, phospho-tau181/amyloid-beta42 ratio, glial fibrillary acidic protein, neurofilament light chain, and two biomarker patterns derived from Principal Component Analysis (PCA1 and PCA2), with higher scores indicating a high level of neurodegeneration and low level of Alzheimer's disease burden, respectively).