Racial discrimination during middle age predicts higher serum phosphorylated tau and neurofilament light chain levels a decade later: A study of aging black Americans

Abstract

Introduction: Recent evidence suggests that exposure to the stress of racism may increase the risk of dementia for Black Americans.

Methods: The present study used 17 years of data from a sample of 255 Black Americans to investigate the extent to which exposure to racial discrimination predicts subsequent changes in serum Alzheimer's Disease Research Center (ADRC) biomarkers: serum phosphorylated tau181(p-tau181), neurofilament light (NfL), and glial fibrillary acidic protein (GFAP). We hypothesized that racial discrimination assessed during middle age would predict increases in these serum biomarkers as the participants aged into their 60s.

Results: Our findings indicate that exposure to various forms of racial discrimination during a person's 40s and early 50s predicts an 11-year increase in both serum p-tau181 and NfL. Racial discrimination was not associated with subsequent levels of GFAP.

Discussion: These findings suggest that racial discrimination in midlife may contribute to increased AD pathology and neurodegeneration later in life.

Highlights: A 17-year longitudinal study of Black Americans. Assessments of change in serum p-tau181, neurofilament light, and glial fibrillary acidic protein. Exposure to racial discrimination during middle age predicted increases in p-tau181 and neurofilament light. Education was positively related to both p-tau181 and exposure to racial discrimination.

Keywords: Alzheimer's disease; Black Americans; dementia; neurodegeneration; neurofilament light; racial discrimination; serum phosphorylated tau181.