Chronic stress, social support, and Alzheimer's blood-based biomarkers in the HABS-HD study

Abstract

INTRODUCTION: High levels of chronic stress and low social support have been associated with worse cognition among older adults, but the underlying mechanisms remain unclear. METHODS: We included 2117 older adults (mean age 65.5 years) enrolled in the Health and Aging Brain Study – Health Disparities (HABS-HD). Linear regression models evaluated the associations between social support or chronic stress and Alzheimer's-related blood-based biomarkers (BBMs), including amyloid beta (Aβ) 42/40 ratio, neurofilament light chain (NfL), phosphorylated tau (p-tau)181, and total tau (t-tau). Interactions between chronic stress or social support and gender or race/ethnicity in relation to BBMs were assessed. RESULTS: Higher chronic stress was associated with higher levels of t-tau. Higher social support was associated with lower levels of NfL. Neither gender nor race/ethnicity modified the associations between chronic stress or social support and BBM levels. DISCUSSION: Chronic stress and social support are associated with BBMs of neurodegeneration. Highlights: Higher chronic stress was associated with higher levels of plasma total tau. Higher social support was associated with lower levels of plasma neurofilament light chain. Neither gender nor race/ethnicity modified the associations between chronic stress or social support and levels of blood-based biomarkers. Chronic stress and social support affect pathways related to neurodegeneration.