China Longitudinal Aging and Cognitive Impairment Study

This is a multi-center longitudinal study that consists of five cohorts: cognitive normal aging (CN), Subjective cognitive impairment (SCI), mild cognitive impairment (MCI), Alzheimer's disease (AD) and vascular cognitive impairment (VCI). The goals of this study are as follow: 1.To establish longitudinal cohort study database containing comprehensive epidemiological data, neuropsychological test data, laboratory parameters, image data and biological samples. 2. To determine the risk factors of AD and other dementias. 3. To explore the conversion rates from CN to SCI, MCI or AD and the risk factors as well as biomarkers for the progression from CN to SCI, MCI or AD. 4. To explore and validate blood, CSF, urine, imaging and other biomarkers for the early detection and progression of AD.