Weathering the Storm of Cognitive Inequities: Testing the Minority Stress and Cognition Model With Indigenous Older Adults

Introduction. The number of Indigenous older adults will more than double in the next thirty years, and they are at high risk of cognitive inequities in later life. Indigenous older adults are underrepresented in health equity and cognitive research. Given this context, do longstanding inequities in education, income, and health create elevated risk for cognitive impairment among Indigenous older adults? This study centers Indigenous older adults among Black, Hispanic, and White peers. It examines whether structural inequities (educational attainment, low incomes), discriminatory experiences (everyday discrimination, major lifetime discrimination), and allostatic loads are associated with racial inequities in cognitive health. Methods: This study used 14 years (2006-2020) of restricted Health and Retirement Study (N = 27,327) data to examine cognitive trajectories among Indigenous, Black, Hispanic, and White older adults with mixed effect growth curve models. Models were adjusted for discrimination experiences and relevant covariates. Allostatic load was tested as a mediator of discrimination experiences and cognitive trajectories. Results: Everyday discrimination experiences were negatively associated with cognition at baseline and over time. Major lifetime discrimination experiences were associated with lower baseline cognition scores and positively with cognitive change over time. Indigenous older adults who experienced high levels of everyday discrimination had lower cognition scores at age than any other race or ethnicity. Allostatic load partially mediated the relationship between discriminatory experiences and cognition across race and ethnicity in unadjusted models but became statistically insignificant in adjusted models. Conclusions and Implications: Indigenous older adults had psychosocial, behavioral, and health profiles associated with a higher risk of cognitive decline in later life; Indigenous older adults report high levels of everyday discrimination, and everyday discrimination was associated with lower cognition at age fifty than Whites, and a steeper rate of decline; and finally, allostatic load did not mediate the relationship between discriminatory experiences and total cognition for any racial or ethnic group. This study enhances our understanding of Indigenous cognitive health inequities and explores potentially modifiable factors for future intervention. Indigenous older adults have a unique profile that places them at elevated risk for cognitive pathology in later life, and structural inequities are powerfully associated with many of these risk factors. Addressing these inequities will require policy and programmatic interventions and inclusion in longitudinal cognitive health research.