Objectives/aims Elevated levels of pro-inflammatory cytokines are associated with a range of mental illnesses, and also with childhood trauma.^1–4 Evidence suggests that inflammation occurring as a result of childhood trauma could play a role in the pathogenesis of psychiatric disorders.^{5 6} However, previous research does not account for confounders, including psychotropic medication and illness duration, that may affect inflammation levels.⁷ The aim of this study was to investigate the relationship between childhood trauma exposure and levels of inflammation in young people with emerging mental health disorders with confounding factors removed.

Methods 10 patients, aged 16–25, with a range of psychiatric disorders and no history of psychotropic medication were recruited from Birmingham mental health services, along with 16 healthy controls. Childhood trauma exposure was assessed with the Childhood Trauma Questionnaire (CTQ), and blood samples were analysed for serum concentrations of pro- inflammatory cytokines IL-6 and IL-1β.

Results There was no significant difference in serum cytokines between patients and healthy controls, or those with and without childhood trauma (p>0.05). Post-hoc sample size calculations estimated 197 patients with and 197 without childhood trauma would be needed to detect a significant 2 pg/ml difference in cytokine levels (80% power, 5% significance). There was a weak positive, but non-significant, correlation between both cytokines and CTQ score in the patient group (rS=0.1–0.3, p>0.05). Multiple linear regression of CTQ score, sex and BMI found that none of these variables significantly predicted cytokine concentration in our population.

Conclusions There is preliminary evidence of an association between childhood trauma and inflammation in patients with mental illness, but due to small sample size no definitive conclusions can be drawn from this data. Future research with a larger sample size and longitudinal approach would be beneficial in establishing whether a relationship exists independent of confounders.

References

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