Psychosocial and Neighborhood Mechanisms and Consequences of Black-White Sleep Disparities on Cognition - AA-White differences have been observed in cognitive performance and risk for cognitive impairment, particularly Alzheimer’s disease and related dementias (ADRD). Few studies have examined how sleep may further explain these disparities, especially considering that sleep disturbances are common in AA adults. Since disparities in cognition and sleep have been observed in middle-aged adults, this portion of the lifespan is ideal to investigate the association between sleep and cognitive decline as well as the underlying psychosocial, contextual, and biomarker factors that influence sleep and/or cognitive AA-White disparities. Every year for 4 years, the proposed study will collect measures of sleep duration and quality, cognitive functioning, inflammatory biomarkers (e.g., CRP, IL-6), life stressors, and resilience factors (e.g., spirituality, coping) in a sample of middle- aged participants from the HANDLS study. The overall objective of this study is to identify mechanisms of AA-White sleep disparities and the mechanisms that account for AA- White differences in ADRD risk. The central hypothesis is that disparities in sleep will be associated with disparities in cognitive decline. Guided by the investigators’ previous research, three specific aims will be tested: 1) To determine if there are differences in the daily coupling of sleep and mobile cognitive performance and whether differences in this coupling are moderated by life stressors (e.g., financial strain and neighborhood disorder); 2) To test longitudinal associations among sleep and performance on mobile cognitive assessments and explore the role of life stressors, protective factors (e.g., spirituality and neighborhood cohesion) and inflammation; 3) To determine whether changes in the strength of the daily coupling of sleep and performance on mobile cognitive assessments relate to differences in traditional clinical measures of cognitive decline over 4 years, and to elucidate the potential mediational role of inflammation. This approach is innovative because it will not only examine the association between sleep and cognitive functioning over time, but will also examine the relationship of life stressors, sleep, inflammatory biomarkers, and/or resilient factors on disparities in cognitive decline. The proposed research is significant because of its potential to identify psychosocial and contextual factors related to impaired sleep and cognition that could serve as the basis for evidence-based behavioral or policy interventions.
