Experience of stress in childhood negatively correlates with plasma oxytocin concentration in adult men

Abstract

Early life experience is known to affect responses to stress in adulthood. Adverse experience in childhood and/or adolescence sensitises to life events that precipitate depression in later life. Published evidence suggests a relationship between depression and oxytocin (OT), but the extent to which early life experience influences OT disposition in adulthood deserves further exploration. This study hypothesised that early life stress (ELS) has a long-term negative effect on OT system activity. The study was performed on 90 male volunteers (18–56 years; mean ± standard deviation = 27.7 ± 7.09 years). Several questionnaires were used to assess: health, early life stressful experiences in childhood (ELS-C, up to 12 years) and early life stressful adolescence (13–18 years), recent stressful life events, depressive symptoms, state–trait anxiety and social desirability. Plasma OT concentration was estimated by means of a competitive enzyme immunoassay. Lower OT concentrations were significantly associated with higher levels of ELS-C (p < 0.01), and with depressive symptoms and trait anxiety (both p < 0.05). The interaction between ELS-C and trait anxiety was significant (p < 0.05), indicating that the link between ELS-C and plasma OT concentration is moderated by trait anxiety. These results contribute to the evidence that early life adverse experience is negatively associated with OT system activity in adulthood, and offer further insight into mediator and moderator effects on this link.

Keywords::

• Anxiety
• coping
• depression
• HPA axis
• oxytocin
• stress

Acknowledgements

This study was supported by School of Human and Life Sciences, Roehampton University, UK (grant number P276). The authors wish to thank Mr Balbir Josen Singh and Mr Donald Fisher for their technical assistance. Preliminary results of this study were presented to the British Neuroscience Association conference (April 2009), Harrogate, UK.

Declaration of interest: The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.