Project Summary The parent RF1 (1 RF1 AG054442-01) provides new data on brain atrophy and Alzheimer’s disease and Related Dementias (ADRD) in two indigenous Bolivian populations, the Tsimane and the Moseten, with extremely low rates of cardiovascular disease (CVD) but high burdens of infection and inflammation. The aims of this project are: (1) Longitudinal assessment of cognitive impairment and dementia in a low cardiovascular disease (CVD) risk population, Tsimane forager-horticulturalists of lowland Bolivia; (2) Neuroimaging to identify brain atrophy correlates of cognitive impairment, AD and other dementias; (3) Characterization of the prevalence of brain atrophy, cognitive impairment, and dementias in the Tsimane; (4) Collect in- depth data on diet and physical activity; and (5) Examine the interaction of inflammation and APOE genotype on cognitive functioning for individual longitudinal change. ADRD prevalence was estimated during the first 2.5 years of NIA funding. Current results indicate a low prevalence (<5%) of dementia after age 70 with no cases of moderate to severe dementia. The two specific aims of this administrative supplement will determine: (1) whether cognitive impairment and dementia are risk factors for SARS-CoV-2 infection and/or morbidity and mortality, if infected; and (2) if Covid-19 results cognitive and neurological aging impairment. The first aim is necessary for interpreting existing data and achieving the original project goals. it is necessary to determine whether those who develop cognitive impairment dementia are at greater risk for COVID-19 mortality in order to control for a potential downward bias in the estimation of dementia incidence. The second aim presents a new unique opportunity to investigate the original project goal of studying impacts of infection on cognitive decline and ADRD. It will evaluate the impact of COVID-19 infection on cognitive function and ADRD incidence.