Project Summary/Abstract Prolonged, elevated inflammation is detrimental to health, with ties to disease and mortality, making prolonged, elevated inflammation an economic burden and public health issue. Daily stressors and affective reactions to daily stressors may be mechanisms that increase risk for prolonged inflammation and downstream health outcomes. Possible pathways through which daily stressors are linked to inflammation remain poorly understood, particularly in older adulthood– when risk for prolonged inflammation is already elevated. Although research identifies daily stress processes (i.e., exposure, severity, affective reactions) as important factors by which stress can affect health, few studies examine how these aspects of daily stress inform inflammation. Those that have examined such associations have focused on middle-aged adults and two indicators of inflammation (C-reactive protein [CRP], interleukin-6 [IL-6]). Recent research also identifies daily stress processes as modifiable targets for addressing gender disparities in health outcomes. The goal of this research is to identify which aspects of daily stress processes – frequency, severity, and affective reactions to daily stressors – are linked with heightened inflammatory biomarkers in older adults, and the extent to which these associations vary between men and women. The proposed research will use data from a recent wave of the Einstein Aging Study (EAS; N=289). A racially diverse sample of older adults (70+ years) participated in a 14- day ecological momentary assessment (EMA) study, with two blood draws pre- and post- EMA period. In addition to eight pro- and anti-inflammatory biomarkers assayed for both basal and stimulated cytokines, the current proposed research will assay one additional cytokine (macrophage migration inhibitory factor [MIF]), theorized to be highly related to psychosocial stress. Aim one will identify how the frequency and severity of daily stressors relate to inflammatory biomarkers. Aim two will determine how both initial (same-day) and prolonged (next-day) affective reactions relate to associations between frequency and severity of daily stressors and inflammatory biomarkers. Aim three will examine gender/sex as a moderator of the associations tested in aims one and two. Current interventions for managing or decreasing prolonged inflammation suggest viable pathways such as medication, or changes in diet and exercise, but not stressors. Findings from this study will provide critical information on what aspects of daily stress processes may be utilized as modifiable psychosocial intervention targets for managing and decreasing prolonged inflammation, and for whom these interventions should be different. In addition, understanding how prolonged affective reactions are linked to inflammation can inform how researchers design intensive repeated measurement studies. The proposed hypotheses will be tested with multilevel structural equation modeling. Dr...