Time trends in suicide-related behaviours in girls and boys.

Abstract

To examine the incidence and nature of emergency department (ED) presentations for nonfatal suicide-related behaviours (SRBs) over time, in boys and girls living in Ontario. We hypothesize declining rates (fiscal years [FYs] 2002/03 to 2006/07) ceased thereafter owing to renewed regulatory warnings against prescribing antidepressants and the economic recession. We graphed and tested differences in ED SRB incidence rates for FYs 2002/03 to 2010/11. We estimated rate ratios and 95% confidence intervals using negative binomial regression controlling for changes in the underlying population (age, community size, and neighbourhood income quintile). We examined the nature of the incident (index) presentations over time in terms of the method(s) used and events occurring before and after the index event. ED SRB incidence rates decreased by 30% in boys and girls from FYs 2002/03 to 2006/07, but not thereafter. This trend was most evident in girls who self-poisoned and in girls' presentations to hospital with mental illness in the preceding year. Within a year of the index event, the proportion of girls with a repeat ED SRB presentation also declined by about one-third, but beyond FYs 2005/06 to 2009/10. However, the proportion admitted subsequent to the index event increased by about one-third. In boys, their patterns of presentations to hospital with mental illness and SRB repetition over time were similar to girls, but estimated with greater variability. While the decline in ED SRB rates to FY 2006/07 is encouraging, the lack of decline thereafter and an increase in subsequent admissions merits ongoing monitoring and evaluation.