Why childhood trauma increases the risk of violence in relationships as we age

This conclusion is based on analysis of data from the Twins Early Development Study (TEDS), a twin study of 12,794 people born in England and Wales.

Source: Pezzoli et al. "Causal and common risk pathways linking childhood maltreatment to later intimate partner violence victimisation", Molecular Psychiatry (2024). DOI: 10.1038/s41380-024-02813-0

TEDS began in 1994 and has lasted for many years, observing twins from early childhood to adulthood. Parents and the twins themselves answer questions and are interviewed about the conditions in which they grew up, as well as their individual behaviour and health. By comparing identical and different twins, researchers can understand how genes and environment influence the formation of abilities and psychological characteristics.

The new study found that people who reported childhood maltreatment (emotional, physical or sexual abuse, and neglect) were three times more likely to experience relationship violence by age 21 compared to those who had no such trauma. By age 26, that likelihood was already four times greater. According to Dr Patrizia Pezzoli (UCL), previous studies have also shown that victims of childhood abuse are three to six times more likely to be victimised by a partner in the future. However, the new finding is that this risk may accumulate as they get older.

The researchers suggest that one reason may be the gradual limitation of social connections in people who have been traumatised as children - because they are more likely to lack safe opportunities to socialise. Together, this increases vulnerability to unhealthy relationships.

To understand why childhood trauma has such a profound impact on later life, the researchers took into account not only individual factors, but also family environment (e.g. socioeconomic status and family environment) and genetics. They found that the general family environment explained 42-43 per cent of the relationship between childhood violence and relationship violence in adulthood, while genes explained 30-33 per cent. Meanwhile, individual factors (friends, personal life experiences, etc.) account for 25-27%.

Dr Pezzoli stresses that understanding these mechanisms will help to develop more targeted prevention and support interventions. The earlier people who have experienced childhood trauma are offered help, the better the chances of avoiding dangerous relationships and developing a healthy living environment.