Relationship of peripheral inflammation and discrimination with memory: a study of Black and Latinx middle‐aged adults

Abstract

AbstractBackgroundMinoritized groups experience higher stress due to structural racism and discrimination. These exposures have been linked to lower cognitive test scores and inflammation is a potential biological pathway underlying this association. Yet studies with multiple inflammatory markers in diverse populations remain limited.MethodWe assessed 635 community‐dwelling adults (mean age = 54.5, SD = 11; 66% women; 67% Latinx, 33% non‐Latinx Black) from the Offspring Cohort. We characterized peripheral inflammation using principal component analysis on 33 serum inflammatory markers. Discrimination was ascertained by the Everyday and Major Discrimination Scales. Episodic memory was measured using the Selective Reminding Test and working memory by the Digit Span Test. Linear models stratified by racialized/ethnic group tested the cross‐sectional relationship between inflammation and memory adjusting for age, sex, and diabetes. Further, we examined if relationship between discrimination and memory (adjusted for age, gender, and education) was attenuated when inflammation was added. Due to smaller sample size, the magnitude of associations corresponding to change in cognitive score associated with >1 year of chronological age, rather than statistical significance, was used to highlight important associations.ResultTwo inflammatory factors were derived, with component 1 including FGF2, Fractalkine, GM‐CSF, IFNg, IL13, MCP3, TNFa, and TNFb, and Component 2 including IFNa2, IL1b, IL1ra, IL5, IL9, and MIP1a. Among Spanish‐speaking participants racialized as Latinx, both inflammatory factors were associated with lower memory scores. Only the first factor was associated with lower memory for English‐speaking participants racialized as Latinx. For participants racialized as Black, only the second factor associated with lower memory. Among Spanish‐speaking Latinx, Everyday Discrimination was associated with lower working memory. Everyday Discrimination was associated with lower episodic memory among Black respondents; this association was attenuated by 20% with inclusion of the inflammatory factor 1 in the models. Several associations that were opposite to hypothesized relationships were observed.ConclusionElevated peripheral inflammation was associated with worse memory among individuals racialized as Black and Latinx. Our results indicate peripheral inflammation may contribute to disparities in cognition and may be one of the ways in which disadvantage due to structural racism and discrimination is embodied among minoritized groups in the United States.