Associations between U.S. County-Level Social Infrastructure and Dementia among Medicare Beneficiaries, 2020.

INTRODUCTION: Spatial and social-environmental factors influence individual cognition and dementia risk, but the role of social infrastructure in geographic dementia disparities remains underexplored. METHODS: We used 2020 Medicare claims data from the Dementia DataHub and 2003-2017 business and establishment data from the National Establishment Time Series Database in spatial autoregressive models to examine associations between county-level social infrastructure and county-level dementia rates. RESULTS: Higher densities of civic organizations were associated with lower county dementia incidence, while museums and recreational facilities were associated with lower prevalence and incidence. Religious organizations were associated with significantly higher rates. County urbanicity moderated the effects of recreational facilities, senior centers, libraries, and coffee shops. DISCUSSION: Types of social infrastructure may help address dementia and related needs by providing social, educational, and other cognitively-protective resources to county residents. Social infrastructure warrants further attention as an area for local investment to reduce geographic disparities in dementia.