Associations between cytokine levels and cognitive function among individuals at clinical high risk for psychosis

Objective

To explore the intricate interplay among cytokines, cognitive functioning, and conversion to psychosis in individuals at clinical high-risk (CHR) for psychosis.

Method

We initially enrolled 385 individuals at CHR and 95 healthy controls (HCs). Subsequently, 102 participants at CHR completed the 1-year follow-up assessments, and 47 participants transitioned to psychosis. We assessed the levels of interleukins (IL-1β, IL-2, IL-6, IL-8, IL-10), tumor necrosis factor-α (TNF-α), granulocyte-macrophage colony-stimulating factor (GM-CSF), and vascular endothelial growth factor (VEGF). We comprehensively evaluated cognitive performance across six domains, including speed of processing (SP), attention/vigilance (AV), working memory (WM), verbal learning (VeL), visual learning (ViL), and reasoning and problem-solving (RPS).

Results

Higher baseline cognitive domain scores were associated with elevated GM-CSF and reduced VEGF levels. In the follow-up analysis, significant time effects were observed for IL-1β and IL-2. We also observed significant interaction effects between specific cognitive domains (AV, WM, VeL, and OCS) and levels of cytokine (GM-CSF, IL-1β, IL-6, and TNF-α). Changes in WM were negatively correlated with changes in TNF-α levels and positively correlated with changes in VEGF levels. Variations in VeL were inversely correlated with changes in GM-CSF and IL-10 levels, whereas changes in RPS were positively associated with changes in GM-CSF and IL-8 levels.

Conclusions

Our results revealed intricate associations among cytokine levels, cognitive performance, and psychosis progression.