Emergency department visits for attempted suicide and self harm in the USA: 2006-2013

To characterise and identify nationwide trends in suicide-related emergency department (ED) visits in the USA from 2006 to 2013.

We used data from the Nationwide Emergency Department Sample (NEDS) from 2006 to 2013. E-codes were used to identify ED visits related to suicide attempts and self-inflicted injury. Visits were characterised by factors such as age, sex, US census region, calendar month, as well as injury severity and mechanism. Injury severity and mechanism were compared between age groups and sex by chi-square tests and Wilcoxon rank-sum tests. Population-based rates were computed using US Census data.

Between 2006 and 2013, a total of 3 567 084 suicide attempt-related ED visits were reported. The total number of visits was stable between 2006 and 2013, with a population-based rate ranging from 163.1 to 173.8 per 100 000 annually. The frequency of these visits peaks during ages 15-19 and plateaus during ages 35-45, with a mean age at presentation of 33.2 years. More visits were by females (57.4%) than by males (42.6%); however, the age patterns for males and females were similar. Visits peaked in late spring (8.9% of all visits occurred in May), with a smaller peak in the fall. The most common mechanism of injury was poisoning (66.5%), followed by cutting and piercing (22.1%). Males were 1.6 times more likely than females to use violent methods to attempt suicide (OR = 1.64; 95% CI = 1.60-1.68; p < 0.001). The vast majority of patients (82.7%) had a concurrent mental disorder. Mood disorders were the most common (42.1%), followed by substance-related disorders (12.1%), alcohol-related disorders (8.9%) and anxiety disorders (6.4%).

The annual incidence of ED visits for attempted suicide and self-inflicted injury in the NEDS is comparable with figures previously reported from other national databases. We highlighted the value of the NEDS in allowing us to look in depth at age, sex, seasonal and mechanism patterns. Furthermore, using this large national database, we confirmed results from previous smaller studies, including a higher incidence of suicide attempts among women and individuals aged 15-19 years, a large seasonal peak in suicide attempts in the spring, a predominance of poisoning as the mechanism of injury for suicide attempts and a greater use of violent mechanisms in men, suggesting possible avenues for further research into strategies for prevention.