The study examined 211 adolescents aged between 12 and 15 years and living in Dublin. 117 of the adolescents had already been identified as being at high risk of having mental health problems. The remaining 94 adolescents, who were matched for gender and recruited from the same local schools, acted as a control group.
All 211 adolescents – and their parents – underwent psychiatric interviews to assess if they had experienced traumatic childhood events. The interview enquired about a number of traumatic events, including physical and sexual abuse, exposure to domestic violence and bullying.
Of the 211 children interviewed, 14 (6.6%) reported experiencing psychotic symptoms, which were mainly auditory and visual hallucinations.
The researchers found that the adolescents who reported psychotic symptoms were six times more likely to have experienced physical abuse than those who did not report such symptoms. In addition, they were ten times more likely to have witnessed domestic violence in their homes.
Adolescents who reported psychotic symptoms were also four times more likely to have experienced sexual abuse but, because the reported rate of sexual abuse in the sample was so small, this difference was not statistically significant.
An association was also found between involvement in bullying and psychotic symptoms, with adolescents reporting such symptoms more likely to be both a bully and a victim of bullying themselves.
The researchers suggest that exposure to traumatic events – such as childhood abuse or domestic violence – may affect the regulation of hormones released by the central nervous system. This can make people more vulnerable to stress and place them at greater risk of future mental illness.
Another theory is that abusive experiences can teach children that people are dangerous, eventually leading to paranoid thoughts and the belief that normal life events are threatening.
The researchers concluded: “Clearly not all individuals who experience severely traumatic events in childhood go on to develop a psychotic disorder…None the less, this paper adds to the evidence that childhood events may be part of a cascade that leads to the development of psychotic symptoms and may ultimately lead to the onset of psychotic illness.”
The abstract of the article can be found here
Reference:
Kelleher I, Harley M, Lynch F, Arseneault L, Fitzpatrick C and Cannon M (2008) Associations between childhood trauma, bullying and psychotic symptoms among a school-based adolescent sample, British Journal of Psychiatry, 193: 378-382
Source: Royal College of Psychiatrists (Press Release)
