The overarching goal of this proposed R21 application is to better understand cognitive impairment and dementia in the LMIC setting of Tumbes, Peru through establishing a baseline of cognitive status for population-based studies of cognitive impairment and dementia in rural communities. Fifty-nine communities in this region have participated in prior research conducted by co-investigators on this application. To attain this goal, we propose the following specific aims: AIM 1: Define the spectrum, type and prevalence of cognitive impairment in Peruvians 60 years of age or older living in rural Northern Peru; AIM 2a: Initiate a population-based cohort of adults with and without cognitive impairment in rural Latin America to facilitate future longitudinal studies of incidence and prevention of cognitive decline and dementia; and Aim 2b: Establish a biomarker and biobanking core, containing information and samples from a large rural population-based cohort of Latin American adults with varying levels of cognitive impairment. This proposal would establish a new collaboration for population-based and clinical research in cognitive impairment, dementia and Alzheimer's disease in a well-established research population in northern Peru with a team of highly experienced investigators in dementia and population health. Although the research tools proposed for this study are well known, they would provide novel information regarding the prevalence of dementia and risk factors for cognitive impairment and dementia at a population-level in a unique rural Latin American population of Northern Peru. We will establish a novel biomarker core in this region with exciting opportunities for future studies of cognitive decline and dementia. Identification of modifiable risk factors could provide therapeutic targets and future opportunities to better understand the influence of metabolism upon cognition over time. In addition, through obtaining information regarding disabilities and quality of life, we will be able to better characterize the impact of cognitive impairment and dementia upon rural Latin American communities - information that currently is not available.