# Inflammation and Cognition: The Moderating Role of Neighborhood Disadvantage

## TL;DR

This study explores how neighborhood disadvantage and inflammation together affect cognitive function in older adults.

## Contribution

The study reveals that the negative impact of inflammation on cognition is stronger in more disadvantaged neighborhoods.

## Key findings

- Higher inflammation was linked to worse cognitive performance in disadvantaged neighborhoods.
- Processing speed and working memory were most affected by the interaction of inflammation and neighborhood disadvantage.
- Tailored interventions are needed for older adults in disadvantaged areas to mitigate cognitive decline.

## Abstract

Extant literature suggests neighborhood disadvantage and inflammation as significant correlates of cognitive function among older adults. However, the joint effects of the contextual and biological factors on cognition have received less attention. The biopsychosocial model of dementia posits that understanding the interplay between biological and socio-contextual determinants of cognition is integral for more effective identification and prevention of Alzheimer’s disease and related dementias (ADRD). Therefore, this study examined whether and how the associations between inflammation and cognition vary by neighborhood disadvantage. Participants were drawn from a subsample of the Elucidating the Necessary Active Components of Training (ENACT, NCT05366023) study that assessed a wide range of biological, psychological, and social factors related to cognitive health from older adults aged 55 to 80 years (N = 51; Mean age=64.3). Inflammation was measured using C-reactive protein (CRP) and cognition was measured using Test My Brain (TMB) tasks. Neighborhood disadvantage was measured using the Area Deprivation Index (ADI). Results showed significant interactions between CRP and ADI for TMB tasks measuring processing speed (Digit Symbol Coding; accuracy) and working memory (Trail Making B; time to completion in milliseconds). Specifically, higher inflammation was associated with worse processing speed (B = -0.01; p < .05) and working memory (B = 8323.66; p < .1) only among those from more disadvantaged neighborhoods. Findings suggest older adults from socioeconomic disadvantaged neighborhoods may be more vulnerable to the cognitive health costs of inflammation, highlighting the need for tailored prevention and intervention efforts that specifically target older adults living in these neighborhoods.