CHILDREN bullied during their early years are up to three times more likely to self-harm than their class-mates when they reach adolescence, a new study shows.
It found around half of 12-year-olds who subject themselves to deliberate injury were frequently picked on.
The research also showed victimised children with mental health difficulties and those from troubled families were at greater risk of resorting to destructive behaviour which could have serious long-term effects in later life.
The study's authors have now called for more effective programmes to prevent bullying in schools.
In a paper, published by the British Medical Journal, they suggest efforts should focus on improving the ways in which children cope with emotional distress.
"Bullying by peers is a major problem during the early school years," they said. "This study found that before 12 years of age a small proportion of children frequently exposed to this form of victimisation already deliberately harmed themselves and in some cases attempted to take their own lives.
"Frequent victimisation by peers increased the risk of self- harm."
The researchers also raised fears over the long-term implications of bullying which, they said, could result in psychological issues, serious injury or death.
"This study adds to the growing literature showing that bullying during the early years of school can have extremely detrimental consequences for some children by the time they reach adolescence," they wrote.
The authors looked at more than 1,000 pairs of twins. The children were assessed on the risks of self-harming in the six months prior to their 12th birthdays.
Data available for 2,141 individuals showed 237 children were victims of frequent bullying and, of that number, 18 (around 8pc) self-harmed. This involved cutting or biting arms, pulling out clumps of hair, a child banging its head against walls or attempting suicide.
Of 1,904 children who were not bullied, 44 (2pc) self-harmed. The research found marginally more girls (52pc) than boys resorted to wounding themselves.
It also showed bullied children with a family member who had either attempted or committed suicide were more likely to self-harm than others.