Cognitive Function, Physical Activity, and Sweat Cytokines in Older Adults With Dementia

Background: Inflammatory cytokines are linked to cognitive function in older adults with dementia; however, their associations with physical activity (PA) and noninvasive biomarkers, such as sweat, remain unclear. Objectives: This study aimed to examine the relationships among cognitive function, PA, and sweat cytokines, as well as the moderating effect of cognitive function on the association between PA and cytokine levels. Methods: Data from 40 older adults with dementia were analyzed to assess correlations between cognitive function, PA measured via wearable devices and sweat cytokine levels. Pearson’s correlation, multiple linear regression, and the Johnson–Neyman method were employed to evaluate these associations. Interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α) levels were measured from sweat samples, and cognitive function was assessed using standardized cognitive tests. Results: PA was positively associated with IL-6 and TNF-α, while lower cognitive function was linked to higher TNF-α levels. Cognitive function moderated the association between PA and TNF‑α; specifically, higher PA was associated with lower TNF‑α levels among participants with moderate-to-severe levels of dementia. Discussion: These findings suggest that sweat cytokine measurement is a viable noninvasive biomarker for inflammatory responses in dementia and that the effect of PA on inflammation may be influenced by cognitive function. Nurses should consider patients’ cognitive function when interpreting the association between PA and cytokine levels.