Bullying by peers can contribute to psychotic symptoms


Bullying in childhood and adolescence is a scourge in sore need of effective solutions. Studies have already revealed the toll that bullying takes on kids’ mental and physical health. Now new research suggests that bullying by peers can increase the risk of the victim developing psychotic symptoms later in life.

The new study, published in the American Journal of Psychiatry, used valuable data from the Environmental Risk Longitudinal Twin Study, which follows 2,232 twin children and their families. Mothers of the children were interviewed and, at age 12, children were asked about bullying experiences and psychotic symptoms, such as hallucinations, delusions or paranoia. The presence of psychotic symptoms was verified by a doctor.

The study found that children who were bullied by peers were more than twice as likely to experience psychotic symptoms at age 12 compared with children who did not suffer similar trauma. This risk remained present even when the researchers controlled for other factors that could contribute to mental illness, such as socioeconomic deprivation, IQ and genetic disposition to mental illness. Children who were bullied and who also experienced maltreatment by adults were more than five times more likely to develop psychotic symptoms. However, enduring a traumatic accident did not significantly increase the risk.


“... All types of trauma were associated with a higher risk for psychotic symptoms at age 12, but the effect was especially strong and consistent across time for trauma characterized by intention to harm,” said the authors, an international group of researchers led by Louise Arseneault from the Institute of Psychiatry in London. It’s possible that this kind of trauma alters a child’s brain development and increases the risk for mental illness, they said.

Psychotic symptoms can develop into full-blown mental illness, the authors note. However, early treatment is thought to be important in curbing the extent and severity of the illness. Doctors who treat children with psychosis should look for evidence of bullying or maltreatment of the child, they said.

In an editorial accompanying the study, Patricia Cohen, a psychiatric epidemiologist with Columbia University, noted that bullying is becoming a bigger problem with the advent of cyber-bulling. “... despite increasing efforts in most developed countries, programs designed to prevent or stop bullying have been far from effective,” she wrote.

Related: Obese kids are bigger targets for bullies, study finds

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