The following is a summary of the “Association between increased serum interleukin-8 levels and improved cognition in major depressive patients with SSRIs,” published in the February 2022 issue of Psychiatry by Cai, et al.

Selective serotonin reuptake inhibitors (SSRIs) can modify the impact of neuroinflammatory cytokines on cognitive deficits in patients with major depressive disorder (MDD). The purpose of this research was to analyze the correlations between IL-8 serum levels and cognitive performance in SSRI-treated major depressive disorder patients. Around 30 patients with MDD treated with SSRIs and 101 healthy controls participated in the trial. Human Inflammatory Cytokine Cytometric Bead Array was used to measure blood IL-8 levels, and the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) was used to assess cognitive function in both patients and controls.

After accounting for confounding factors, the RBANS test scores of MDD patients using SSRIs were significantly lower than those of healthy controls (all P< 0.001). When taking into account confounding factors, serum IL-8 levels were greater in MDD patients using SSRIs compared to healthy controls (F = 3.82, P < 0.05). It was found that in MDD patients taking SSRIs, serum IL-8 levels positively correlated with delayed memory (r = 0.37, P = 0.04) and visuospatial/constructional (r = 0.43, P = 0.02) sub-scores, but not in healthy controls (delayed memory score: r = -0.12, P = 0.24; visuospatial/constructional score: r = 0.02, P = 0.81).

Their results suggested that an increase in blood IL-8 level may correspond to improved MDD delayed memory and visuospatial/constructive function and may potentially be involved in the psychopathology of MDD or the usage of SSRIs.

Source: bmcpsychiatry.biomedcentral.com/articles/10.1186/s12888-023-04616-z