MedWire News: Children who experience physical abuse, exposure to domestic violence, and involvement in bullying are more likely to report psychotic symptoms in early adolescence than those with no childhood trauma, study results show.

The study’s authors stress, however, that not all individuals who experience severely traumatic events in childhood go on to develop a psychotic disorder.

“Disease causation is a dynamic process and should be considered in terms of a pathway over a life course rather than in terms of a certain set of risk factors at a point in time,” Mary Cannon (The Royal College of Surgeons in Ireland, Dublin) and colleagues comment.

Although many previous studies have implicated childhood trauma in subsequent psychosis, most have been based on treatment samples using retrospective assessment of trauma, leaving them open to recall bias, say the researchers.

To redress this, they carried out psychiatric interviews to assess psychotic symptoms among 211 adolescents aged between 12 and 15 years who had not previously had contact with the mental health services.

The researchers asked participants about a number of early traumatic events during childhood including physical and sexual abuse, exposure to domestic violence, and bullying.

Overall 14 (6.6%) adolescents interviewed reported experiencing at least one psychotic symptom.

Those adolescents who did report psychotic symptoms were six times more likely to have experienced childhood physical abuse and 10 times more likely to have witnessed domestic violence as a child than were adolescents who did not report such symptoms. The results were significant after taking into account comorbid psychiatric illness or a family history of psychiatric illness.

Adolescents who reported psychotic symptoms were four times more likely to have experienced childhood sexual abuse but, given the low absolute numbers of those who reported sexual abuse, this difference was not statistically significant.

Notably, adolescents with psychotic symptoms were not significantly more likely to have been victims of bullying, but were a significant 10 times more likely to have been perpetrators of bullying than adolescents who did not report such symptoms.

Writing in the British Journal of Psychiatry, Cannon and co-workers comment: “This paper adds to the evidence that traumatic childhood events may be part of a cascade that leads to the development of psychotic symptoms and may ultimately contribute to the onset of psychotic illness.”

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