Identification of young females at high risk of suicide following hospital-treated self-harm in Victoria, Australia

Objective: We conducted a data linkage study in Victoria, Australia, to determine the proportion of young females who are treated in hospital for self-harm who go on to die by suicide within 5 years and to identify factors associated with increased suicide risk in this same cohort. Method: We undertook a cohort study following 3689 female patients aged 10-24 years, who were initially treated in hospital for self-harm during the 2-year period January 2011 to December 2012. We followed each patient for 5 years unless they died first, in which case, they were followed until their date of death. We used inpatient admissions from the Victorian Admitted Episodes Dataset and emergency department presentations from the Victorian Emergency Minimum Dataset linked to death data from two sources, the Victorian Suicide Register and the National Death Index. Results: Twenty-eight individuals (0.76% of the total cohort) died by suicide within 5 years of their index admission. In multivariate survival analysis, only suicide ideation at the time of self-harm (hazard ratio = 4.59; 95% confidence interval: 1.70, 12.38) and a decreasing time between successive self-harm episodes (hazard ratio = 4.38; 95% confidence interval: 1.28, 15.00) were associated with increased suicide risk. Conclusion: Although the vast majority of young females who present to hospital for self-harm do not die by suicide within 5 years, our results suggest young females expressing suicide ideation and those presenting frequently with decreasing time between successive episodes should be prioritised for suicide-prevention efforts.