Therefore, the aim of this study was to investigate the association of APOE4 and two PRSs based upon training sets, which utilize differing AD definitions, with incident AD and all-cause dementia (ACD) diagnosis within 17 years as well as with levels of the AD-related blood biomarkers, phosphorylated tau181 (P-tau181), neurofilament light (NfL), and glial fibrillary acidic protein (GFAP) at baseline before dementia diagnosis in a community-based cohort study. This evidence concerns the gene APOE and Alzheimer disease.