Perceived Stress is Associated with Alzheimer's Disease Cerebrospinal Fluid Biomarkers in African Americans with Mild Cognitive Impairment.

BACKGROUND: African Americans (AA) have a higher Alzheimer's disease (AD) prevalence and report more perceived stress than White Americans. The biological basis of the stress-AD link is unclear. This study investigates the connection between stress and AD biomarkers in a biracial cohort. OBJECTIVE: Establish biomarker evidence for the observed association between stress and AD, especially in AA. METHODS: A cross-sectional study (n = 364, 41.8% AA) administering cognitive tests and the perceived stress scale (PSS) questionnaire. A subset (n = 309) provided cerebrospinal fluid for measurement of Aß42, Tau, Ptau, Tau/Aß42 (TAR), and Ptau/Aß42 (PTAR). Multivariate linear regression, including factors that confound racial differences in AD, was performed. RESULTS: Higher PSS scores were associated with higher Ptau (ß= 0.43, p = 0.01) and PTAR (ß= 0.005, p = 0.03) in AA with impaired cognition (mild cognitive impairment). CONCLUSION: Higher PSS scores were associated with Tau-related AD biomarker indices in AA/MCI, suggesting a potential biological connection for stress with AD and its racial disparity.