Are cytokine profiles associated with the cognitive performance of adults with severe major depression?

Cognitive impairment often occurs in major depressive disorder (MDD). Studies suggest that these cognitive deficits may be associated with inflammatory biomarkers, but data are limited. Therefore, this study aims to investigate the relationship between 48 peripheral blood cytokines and cognitive performance in patients with severe depressive disorder. One hundred consecutive hospitalized adult patients with severe depression who participated in the Depression long-term Augsburg (DELTA) study were included in the present analysis. To test working memory (WM) the Wechsler Adult Intelligence Scale (WAIS) IV and to assess interference control (IC) the Stroop Color and Word Test (SCWT) were performed. The serum concentrations of the biomarkers were measured using the Bio-Plex ProTM Human Cytokine Screening Panel 1. Multiple linear regression models adjusted for possible confounders were fitted to examine associations. WM was impaired in 11% of the patients. IC was impaired in 1%-3% of the cases depending on the subtest. Eotaxin, IL-1(i, IL-4, MCP-1, G-CSF, and PGF-BB were negatively associated with the WM. Eotaxin, IL-1(i, IL-4, IL-16, IL-18, MCP-1, G-CSF, SCF, and MIP-1 alpha were negatively associated with IC. None of these associations remained significant after adjustment for multiple testing. The present study identified eotaxin, IL-1(i, IL-4, IL-16, IL-18, MCP-1, G-CSF, SCF, PGF-BB and MIP-1 alpha as being associated with cognitive performance. After confirmation of these results in further studies, these cytokines may be potential targets for new treatments.

Automated summary

This study investigated the relationship between peripheral blood cytokines and cognitive performance in patients with severe depressive disorder. The results identified several cytokines that were associated with cognitive performance, but these associations did not remain significant after adjustment for multiple testing. With further research, these cytokines may become potential targets for new treatments.