Self-harm in youth trends according to sex; varies geographically

Researchers have found sex differences in youth who self-harm in some regions of the world, but not others, providing more insight for researchers and clinicians to more effectively treat it.

“Self injury is a strong predictor of suicide attempts and its prevalence has been increasing among girls in North America and Europe, but less has been known about trends in other geographical regions of the world and we sought to learn more,” says Dr. Rachel Mitchell, senior author of a new study and an associate scientist and psychiatrist at Sunnybrook Health Sciences Centre.

The study, published in the June 14, 2024 issue of the journal JAMA Network Open, used a meta-analysis approach of 38 studies from across 17 countries involving 266,491 participants with a pooled prevalence of non-suicidal self injury of 17.7 per cent amongst adolescents aged 10-19.

The results found that female adolescents are twice as likely to engage in non-suicidal self harm than male adolescents in North America and Europe, but not in Asia where self-harm is shown to be fairly equal between the sexes.

“It’s important for those of us in the field of psychiatry – both on the clinical and research ends – to better understand why non-suicidal self injury is considerably more prevalent in teenage girls versus teenage boys in some regions of the world and not others so that we can work towards more effective prevention and treatment approaches for this behaviour among all adolescents,” says Dr. Mitchell, also an assistant professor in the Department of Psychiatry at University of Toronto.

While the reasons for the differences remain unclear, the authors suggest treatments may need to be more regionally, and possibly culturally-specific, to better target different sexes among youth in the prevention and treatment of self-harming behaviours, and to better understand the possible interplay with corresponding regional trends in suicide. The studies reviewed did not assess for non-binary gender identities.

“Future research with sex-, gender-, region-, and culture-specific lenses will be essential in clarifying how and why these behaviours differ by sex and gender in different regions,” says Dr. Fiona Moloney, first author of the study and psychiatry resident in the Department of Psychiatry at University of Toronto. “Research in this area will be foundational in developing and evaluating effective interventions for all adolescents engaged in non-suicidal self injury, regardless of location, sex and gender.”