Abstract # 1826 Dynamical association between day-to-day fluctuations in inflammatory markers and affect in healthy individuals

Several studies show an effect of cytokine levels on affect, and vice versa. However, most studies have a cross-sectional study design, therefore it is impossible to study causality between inflammation and affect, in contrast to idiographic studies. The main goal of this study is to explore the effects of 8 inflammatory markers on positive affect (PA) and negative affect (NA) in an idiographic study design. 10 healthy individuals (3 males, 7 females; age 21–58) filled out the PANAS and collected 24-h-urine for 63 consecutive days. Multiplex analyses were used to quantify levels of C-reactive protein (CRP), Fractalkine, Interleukin-1 receptor-antagonist (IL-1RA), interferon-alpha (IFNalpha), interferon-gamma (IFNgamma), Interferon gamma-induced protein 10 (IP-10), Macrophage inflammatory protein-1beta (MIP-1beta), and Vascular Endothelial Growth Factor (VEGF) in 24-h-urine. First order unified structural equation models (uSEM) were fitted for each individual and each marker, adjusted for exercise, smoking and alcohol use. Preliminary analyses showed different associations for each individual between inflammatory markers and affect. CRP was negatively associated with PA in one individual, Fractalkine showed opposite associations in 3 individuals. In addition, IFNalpha showed opposite associations in two other individuals. IFNgamma, IL1RA, MIP1beta and VEGF were mainly negative associated with PA. Our results suggest that pro- and anti-inflammatory markers influence levels of PA and NA, in healthy individuals. Future research should reveal the role of inflammatory markers as messengers in healthy individuals.