Researchers from Australia have published the first population based study to chart the incidence of self harm during the transition from late adolescence through to adulthood.

They recruited a stratified random sample of 1,943 teenagers from 44 schools across Victoria over a 16 year period (1992-2008). Participants were given questionnaires and telephone interviews and followed up on 7 separate occasions, first when they were 15.9 years old (SD 0.49), through to when they were 29 years old (SD 0.59).

They obtained ‘summary adolescent measures’ for:

• Cannabis use
• Cigarette smoking
• High-risk alcohol use
• Depression and anxiety
• Antisocial behaviour
• Parental separation or divorce

Here’s what they found:

• 8% reported self-harm in adolescence
• More girls (10%) than boys (6%) reported self harm (risk ratio 1·6, 95% CI 1·2-2·2)
• A substantial reduction in the frequency of self-harm was reported during late adolescence. 82% of those who reported self-harm during adolescence reported no further self-harm in young adulthood, with a stronger continuity in girls (13/888) than boys (1/764)
• During adolescence, incident self-harm was independently associated with
  • Symptoms of depression and anxiety (HR 3·7, 95% CI 2·4-5·9)
  • Antisocial behaviour (1·9, 1·1-3·4)
  • High-risk alcohol use (2·1, 1·2-3·7)
  • Cannabis use (2·4, 1·4-4·4)
  • Cigarette smoking (1·8, 1·0-3·1)
• Adolescent symptoms of depression and anxiety were clearly associated with incident self-harm in young adulthood (5·9, 2·2-16)

The researchers concluded:

Most self-harming behaviour in adolescents resolves spontaneously. The early detection and treatment of common mental disorders during adolescence might constitute an important and hitherto unrecognised component of suicide prevention in young adults.

Moran, P et al. The natural history of self-harm from adolescence to young adulthood: a population-based cohort study. The natural history of self-harm from adolescence to young adulthood: a population-based cohort study. The Lancet – 17 November 2011. DOI: 10.1016/S0140-6736(11)61141-0 [Abstract]