A new study from St. Michael's Hospital found that, after four years of declining, the rates of teenagers coming into Ontario emergency departments with suicide-related behaviours stopped dropping between 2006 and 2010.

Suicide-related behaviours are incidents of self-inflicted injuries or self-poisonings.

Using data from the Institute for Clinical Evaluative Sciences, the researchers found that from 2002 to 2006, the rates of teenagers coming into Ontario emergency departments with suicide-related behaviours declined by 30 per cent. However, from 2006 until the end of the study in 2010, rates did not continue to drop and about one-third more of these events resulted in a hospital admission, suggesting an increase in severity.

"Coming into hospital with a self-inflicted injuries or poisoning is a strong risk factor for suicide," said Dr. Anne Rhodes, lead author and research scientist in St. Michael's Hospital's Suicide Studies Research Unit. "Within a year of coming into a hospital with suicide-related behaviour, 16 per cent will repeat their behaviour and about two per cent will die by suicide."

Previous research from Dr. Rhodes has shown that more than 80 per cent of youth who die by suicide had some form of contact with the health care system in the year before their death. Compared to population-based peers, youth who have gone to an emergency department to hospital with suicide-related behaviours had three to four times higher risk of death.

The study, published in The Canadian Journal of Psychiatry, outlines potential factors contributing to the declines between 2002 and 2006 - including the increased efforts made by some groups to reduce stigma about mental illness and seeking help; or reductions in alcohol consumption and misuse among youth.

While unable to specifically account for the change in rates after 2006, researchers suggest that the economic recession and FDA regulatory warnings against prescribing antidepressants may have halted further declines in the rates of suicide-related behavior and led to the increase of hospital admissions. The findings show that rate changes were not explained by shifts in the population age, community size or income structures.

In Ontario, the FDA warning and recession coincided with the introduction of Local Health Integration Networks in 2006. Previous research from around the world suggests that during times of economic and regulatory pressures suicide-related behavior rates often increase. It's possible that the LHINs helped to level emergency department suicide-related behaviour rates during this period when rates could have been increasing.

Dr. Rhodes and her team also reported on gender differences between suicide and suicide-related behaviours and confirmed that girls are more likely to exhibit suicide-related behaviours, particularly in youth, whereas it is known that boys are more likely to die by suicide.

"Because girls are more likely to come to emergency departments with suicide-related behaviours than boys, they may actually reduce their suicide risk by interacting with the system more frequently," said Dr. Rhodes.

Self-poisoning was the most common method of suicide-related behaviours for boys (62.2 per cent) and girls (74.1 per cent) and cut-pierce injuries were the next most common for both groups.

In Canada, suicide is the second-leading cause of death in youth - nearly one quarter of all deaths for those aged 15-19 years.