Bullying can lead to mental illness, says study

Bullying can increase the risk of children suffering from psychotic symptoms by up to four times, researchers revealed today.

Effects included hallucinations, paranoid delusions – such as believing they are being spied on – and irrational thought.

Psychologists followed 6,437 children from birth to 13 years. The children took part in annual face-to-face interviews, as well as psychological and physical tests. Parents were also asked to complete questionnaires about their sons' and daughters' development.

At the age of 13, the children were interviewed about their experiences of psychotic symptoms in the previous six months. Those who suffered physical or emotional bullying were twice as likely to develop psychotic symptoms by early adolescence as children who were not bullied. Children who experienced sustained bullying over a number of years could be four times more at risk.

Professor Dieter Wolke said: "Our research shows adverse social relationships with peers may increase the risk of developing psychosis in adulthood."