The Diagnostic Cut-off Value of Core Biomarkers of Alzheimer's Disease

1. Incorporating patients who meet the criteria from Capital Medical University Xuanwu Hospital including AD, aMCI, non-AD dementia and cognitively normal control. 2. Collect the information of clinical and neuropsychological assessment (mini-mental state examination, MMSE, Montreal cognitive assessment, MoCA, and clinical dementia rating scale, CDR), neuroimaging data including medial temporal atrophy (MTA) score, Fazekas score, MRI, and PET(optional), as well as the biological sample, such as CSF and peripheral blood. 3. To quantify levels of Aβ42, Aβ40, t-tau, p-tau, inflammatory factors, etc. in CSF and blood. 4. Detect all participants ApoE genotype. 5. Independently establish the best cut-off value of Chinese people in our laboratory. 6. Analysis the relationships between core biomarkers in CSF/blood and ApoE genotype and neuroimaging data. 7. Establish combined diagnostic model.