A – 91 The Roles of IL-6 and IL-10 in Adult Cognitive Function

Abstract Objective Interleukin-6 (IL-6), a pro-inflammatory cytokine, is linked to cognitive decline in older adults. However, its role in cognitive functions remains poorly understood. Thus, this study investigated interleukin-10 (IL-10), a key anti-inflammatory cytokine known for down-regulating IL-6 activity to help clarify the mixed findings. Specifically, we utilized hierarchical regressions to investigate the respective contributions of IL-6 and IL-10 to memory and executive function, adjusting for demographic factors and markers of obesity (Waist-Hip ratio: WHR and Body Mass Index: BMI). Method Data from 1,134 adults (M = 57.75 years, SD = 11.61; 57% Female; 81% White) included in the Midlife in the United States (MIDUS) 2 study was used to examine serum levels of IL-6 and IL-10 with episodic memory and executive functioning. Participant age at clinic visit, WHR, and BMI were covariates in the model. Results IL-10 (β=-.068, p=.016), but not IL-6 (β=.001, p=.966), was significantly associated with episodic memory when adjusting for covariates, with the overall model accounting for 13.1% of the variance. In contrast, after adjusting for the covariates, IL-6 (β=-.094, p=.003) but not IL-10 (β=.004, p=.883) was significantly associated with executive function, with the overall model accounting for 12.7% of the variance. Conclusion Results revealed differential associations between cognitive functions and the inflammatory markers IL-10 (anti-inflammatory) and IL-6 (pro-inflammatory). While highly speculative, these findings potentially point to domain-specific impacts of low IL-10 and high IL-6. Future work intends to examine the distinctive roles of inflammatory markers in cognitive aging.