The impact of adverse interpersonal experiences (AIE) on mild cognitive impairment (MCI) and risk for Alzheimer's disease and related dementias (ADRD) in ethnically diverse twins

ABSTRACT Age-related decline in cognitive health is a pressing public health concern. Variation in late-life adult cognitive health is associated with adverse interpersonal experiences (AIEs, e.g., loneliness), although documenting the full extent of this association requires further study of a greater diversity of AIEs. Social isolation and lower quality relationships, characterized by greater conflict, tend to disrupt psychosocial and biological functioning, resulting in increased risk for Mild Cognitive Impairment (MCI), which, in turn, increases risk for Alzheimer’s Disease and Related Dementias (ADRD). Conversely, adults who receive more warmth, support, and responsiveness in their social experiences typically have better cognitive outcomes. This project takes advantage of an unparalleled opportunity to further this important line of work on the significance of relationship experiences in later adulthood for MCI by conducting a follow-up of the Minnesota-Carolina Twin Study of Aging (MCTSA). MCTSA is a longitudinal study targeting 800 ethnically diverse monozygotic and dizygotic same-sex twin pairs. Most twin participants have already completed assessments of AIEs in the previous project period. In this proposed continuation period, we will complete novel assessments of MCI. Further, a daily diary study aimed at connecting AIEs and fluctuations in cognitive functioning on a day-to-day timescale will allow us to document processes that presage the development of Alzheimer’s Disease and Related Dementias (ADRD). Our overarching objectives are to investigate the degree to which diverse AIEs predict subsequent MCI, to take advantage of the twin aspect of our design to document the environmental basis for AIE-MCI associations, and to understand how these connections are manifest in the day-to-day flow of interpersonal experiences and cognitive functioning. Specific aims of this project include: AIM 1: Document longitudinal associations between a comprehensive array of earlier, specific adverse interpersonal experiences (AIE) and subsequent mild cognitive impairment (MCI); AIM 2: Model environmental pathways linking earlier adverse interpersonal experiences (AIE) and subsequent MCI; AIM 3: Complete a twin daily diary study of within-person dynamics connecting adverse interpersonal experiences and daily fluctuations in cognitive functioning.