Most suicides in an almost nine-year Ontario study occurred after a first attempt, pointing to the need for longer-term monitoring, doctors say in a new report published Wednesday.

The study tracked more than 65,000 children and adults between April 2002 and December 2010 who went to an emergency department in the province for a first self-poisoning. It compared them with controls of the same age and sex. 

Suicide is the second-leading cause of death among people aged 15 to 35, according to Statistics Canada.

Over an average of five years of follow-up, 976 people out of the 65,784 or nearly 1.5 per cent of those who were discharged for a first poisoning eventually took their own lives, the researchers reported in Wednesday's issue of JAMA Psychiatry.

Their risk of suicide was 40 times higher than the general population, according to what Sick Kids calls the largest suicide prevention study worldwide.

Suicide prevention focuses on the immediate post-attempt period, but the facts suggest the success is limited. In the U.S., suicide rates have increased by more than 16 per cent during the past decade, the researchers said.

High-risk group

"Because the suicide risk is durable over many years after the first attempt, we believe the prevention initiatives should be sustained over many years," said Dr. Yaron Finkelstein, lead author of the study, an associate professor of pediatrics, pharmacology and toxicology at the University of Toronto and a staff physician at the Hospital for Sick Children.

The implication is that suicide prevention efforts such as offering psychiatric resources should be sustained among the high-risk group of people who survived a first self-poisoning, said the study's senior author, Dr. David Juurlink, head of clinical pharmacology and toxicology at Sunnybrook Health Sciences Centre in Toronto.

Self-poisoning "may not just be a one-time event," Finkelstein said. "It may signify the way that they're managing their stresses in life generally, and that's probably why the risk is durable over many years."

Alicia Raimundo, a mental health advocate in Toronto who herself first had thoughts of suicide at age 12, sees the value of longer monitoring.

She told CBC News that for her, "it got to point where walls were up so high around me nobody knew who I was any more. That's when I really started to realize how upset I was and how sad I was.That was the first time I started to think about suicide."

Felt ashamed

After a suicide attempt, Raimundo was at a care centre when another client handed her a silver necklace with "hope" on it. 

"I promised a lot of care people I was going to get support, but I didn't, because I just felt really ashamed about needing that," she said.

In university, she said, she realized the value of therapy, in part through the support of her friends and family.

For her, the message from the research findings lie in finding the best ways to engage in care through therapy, medication and appropriate check-ins.

Lowering suicide rates in Canada requires continuing, high-quality mental health care where the research shows the risk is "exceedingly high" — among those who have a mental illness and who have attempted suicide, ​said Dr. Stan Kutcher, professor of psychiatry at Dalhousie University in Halifax and a recognized expert in suicide.

"We will save lives, very importantly," Kutcher said.

"We will also save people being admitted to hospital with an attempt that did not lead to death, so we will save that chaos in their lives and in the lives of their families. … We will also save money in the health-care system."

The study was funded by the Canadian Institutes of Health Research and the Ontario health ministry's Institute for Clinical Evaluative Sciences.

With files from CBC's Melanie Glanz and Diane Paquette