London, May 13 (IANS): Children with autism face a greater risk of eating disorders, say researchers, adding that autistic traits in childhood come before behaviours characteristic of eating disorders, and so could be a risk factor for developing eating disorders.

Previous research has found that autism and eating disorders can occur together, as 20-30 per cent of adults with eating disorders have autism, and 3-10 per cent of children and young people with eating disorders.

"We have found that young children with autistic traits at age seven are more likely than their peers to end up developing eating disorder symptoms in adolescence," said study lead author Dr Francesca Solmi from University College London in the UK.

The study, published in the Journal of Child Psychology and Psychiatry, involved 5,381 adolescents who have been participating in longitudinal research from birth as part of the University of Bristol's Children of the 90s cohort study.

The researchers considered whether they had autistic social traits at age 7, 11, 14 and 16, and disordered eating (fasting, purging, prolonged dieting, or binge-eating) at age 14.

They investigated autistic traits reported by the mother, rather than a diagnosis of autism, meaning that the study findings would involve children who do not necessarily have autism but also would include children with autism who might not have been diagnosed.

In the study group, 11.2 per cent of girls reported at least one disordered eating behaviour within the previous year (7.3 per cent experience them monthly and 3.9 per cent weekly), compared to 3.6 per cent of boys (2.3 per cent monthly and 1.3 per cent weekly).

Adolescents with eating disorders showed higher levels of autistic traits by age seven, suggesting that the autistic traits predated the disordered eating (as eating disorders are very rare at age seven), and therefore might pose a risk factor for eating disorders.

Children who displayed higher autistic traits at age seven were 24 per cent more likely to have weekly disordered eating behaviours at age 14.

Further analysis confirmed that eating disorders at age 14 did not appear to increase autistic traits by age 16.

While the study did not investigate the reasons behind the relationship, the researchers point out that children with autism may have difficulties with social communication and developing friendships, which could contribute to higher rates of depression and anxiety at young ages.

Disordered eating might result from dysfunctional methods of coping with these emotional difficulties, the study noted.