Childhood trauma and adulthood inflammation: A meta-analysis of peripheral C-reactive protein, Interleukin-6 and Tumour Necrosis Factor-α

Abstract

Childhood trauma confers higher risk of adulthood physical and mental illness, however the biological mechanism mediating this association remains largely unknown. Recent research has suggested dysregulation of the immune system as a possible biological mediator. The present paper conducted a meta-analysis in order to establish whether early life adversity contributes to potentially pathogenic pro-inflammatory phenotypes in adult individuals. A systematic search of Pubmed, PsycINFO, EMBASE, Scopus and Medline identified 25 articles for the meta-analysis, including 18 studies encompassing a sample of 16,870 individuals for C-reactive protein (CRP), 15 studies including 3,751 individuals for interleukin-6 (IL-6), and 10 studies including 881 individuals for tumour necrosis factor-α (TNF-α). Random-effects meta-analysis showed that individuals exposed to childhood trauma had significantly elevated baseline peripheral levels of CRP (Fisher’s z = 0.10, 95% confidence interval [CI] = 0.05 – 0.14), IL-6 (z = 0.08, 95% CI = 0.03 - 0.14) and TNF-α (z = 0.23, 95% CI = 0.14 – 0.32). Subgroup analyses for specific types of trauma (sexual, physical or emotional abuse) revealed that these impact differentially the single inflammatory markers. Moreover, meta-regression revealed greater effect sizes in clinical samples for the association between childhood trauma and CRP but not for IL-6 or TNF-α. Age, BMI and gender had no moderating effects. The analysis demonstrates that childhood trauma contributes to a pro-inflammatory state in adulthood, with specific inflammatory profiles depending on the specific type of trauma.