The involvement of alcohol in hospital-treated self-harm and associated factors: findings from two national registries.

Background Alcohol is often involved in hospital-treated self-harm. Therefore it is important to establish the role of alcohol in self-harm as well as to identify associated factors, in order to best inform service provision. Methods Data on self-harm presentations to hospital emergency departments in Ireland and Northern Ireland from April 2012 to December 2013 were analysed. We calculated the prevalence of alcohol consumption in self-harm. Using Poisson regression models, we identified the factors associated with having consumed alcohol at the time of a self-harm act. Results Alcohol was present in 43% of all self-harm acts, and more common in Northern Ireland (50 versus 37%). The factors associated with alcohol being involved were being male, aged between 25 and 64 years, and having engaged in a drug overdose or attempted drowning. Presentations made out-of-hours were more likely to have alcohol present and this was more pronounced for females. Patients with alcohol on board were also more likely to leave without having been seen by a clinician. Conclusions This study has highlighted the prevalence of alcohol in self-harm presentations, and has identified factors associated with presentations involving alcohol. Appropriate out-of-hours services in emergency departments for self-harm presentations could reduce the proportion of presentations leaving without being seen by a clinician and facilitate improved outcomes for patients.