The iceberg of suicide and self-harm in Irish adolescents: A population-based study

Abstract

Purpose Suicide is a leading cause of death among adolescents. Self-harm is the most important risk factor for suicide, yet the majority of self-harm does not come to the attention of health services. The purpose of this study was to establish the relative incidence of adolescent suicide, hospital-treated self-harm and self-harm in the community. Methods Annual suicide rates were calculated for 15-17 year-old in the Cork and Kerry region in Ireland based on data from the Central Statistics Office. Rates of hospitaltreated self-harm were collected by the Irish National Registry of Deliberate Self-Harm. Rates of self-harm in the community were assessed using a survey of 3,881 adolescents, the Child and Adolescent Self-harm in Europe study. Results The annual suicide rate was 10/100,000. Suicide was six times more common among boys than girls. The annual incidence rate of hospital-treated self-harm was approximately 344/100,000, with the female rate almost twice the male rate. The rate of self-harm in the community was 5,551/100,000, and girls were almost four times more likely to report self-harm. For every boy who died by suicide, 16 presented to hospital with self-harm and 146 reported self-harm in the community. For every female suicide, 162 girls presented to hospital with self-harm and 3,296 reported self-harm. Conclusions Gender differences in relative rates of selfharm and suicide are very large, with boys who have harmed themselves at particularly high risk of suicide. Knowledge of the relative incidence of self-harm and suicide in adolescents can inform prevention programmes and services.