Linking childhood trauma and cytokine levels in depressed adolescents

Background: Evidence supports raised circulating levels of inflammatory mediators, such as interleukin-6 (IL-6) and tumor necrosis factor (TNF alpha), among clinically depressed adults, although preliminary findings in adolescents are mixed. Independently, meta-analyses identify correlations between childhood trauma and elevated cytokine levels in adulthood. Here, we examine the possible role of individual differences in exposure to childhood trauma in contributing to variability in cytokine levels in depressed adolescents. Methods: 52 depressed adolescents and 20 healthy adolescents completed measures of childhood trauma and provided blood for the assessment of plasma IL-6 and TNF alpha. Cross-sectional associations of childhood trauma and cytokine measures were assessed in both depressed and healthy adolescents, along with exploratory analysis of childhood trauma subtypes. Longitudinal relationships between childhood trauma and cytokine measures were also studied in an exploratory fashion within a subset of depressed participants (n = 36). Results: Higher childhood trauma (particularly emotional abuse) was positively associated with TNF alpha in depressed adolescents. Childhood trauma was not linked to longitudinal changes in cytokine levels. Discussion: In depressed adolescents, childhood trauma may relate to higher levels of the proinflammatory cytokine TNF alpha and contribute to heterogeneity in cytokine elevation among depressed adolescents. Such findings may ultimately help guide more effective individualized treatments for adolescents with depression.

Automated summary

This study found a positive association between childhood trauma, particularly emotional abuse, and elevated levels of the proinflammatory cytokine TNF alpha in depressed adolescents. However, no longitudinal relationship was found between childhood trauma and cytokine levels. These findings suggest that childhood trauma may contribute to heterogeneity in cytokine elevation among depressed adolescents.