Deliberate self-inflicted trauma: population demographics, the nature of injury and a comparison with patients who overdose.

Self-inflicted harm, whether by trauma or drug overdose, is not uncommon, and has important social consequences. This study was a retrospective record analysis of patients who presented to an emergency department after deliberate self-inflicted harm. Over the two-year study period, there were 175 self-inflicted trauma and 441 overdose presentations. The self-inflicted trauma patients were a heterogeneous group and included patients who displayed suicide-related behaviour and behaviour not related to suicide. The self-inflicted traumatic injuries tended to be either relatively minor or potentially very serious. Lacerations to the upper limb were seen most frequently. The trauma and overdose groups were almost mutually exclusive populations and showed some significant differences. The trauma group was smaller, contained a significantly greater proportion of younger patients and males, presented more commonly in the late evening and early morning hours and ultimately received less psychiatric counselling. Research of this type has problems of underreporting and data bias. Prospective studies of self-inflicted trauma would improve the identification of patients after self-harm and improve the understanding of the relationship between the patterns of injury psychiatric diagnosis and the long-term risk of future self-harm.