Teen suicides in Manitoba rose sharply following antidepressant warnings
April 8, 2008

TORONTO (Canadian Press) ? A Health Canada warning that linked newer generation antidepressant drugs with suicidal thoughts in children and teens may have had an unintended and negative consequence, a new study suggests.

Suicides in children and teens in Manitoba rose by 25 per cent in the two years after Health Canada and the U.S. Food and Drug Administration warned that children and adolescents who took selective serotonin reuptake inhibitors, or SSRIs, might be at increased risk of experiencing suicidal thoughts.

"It's a very big jump. And that's why we wanted to put this data out there," said lead author Dr. Laurence Katz, a child and adolescent psychiatrist and a professor at the University of Manitoba.

As well, SSRI use in children and teenagers dropped by 14 per cent. And doctors registered a 10 per cent decline in appointments for treatment of depression in children and teenagers.

"We have no reason to believe that depression rates in Manitoba dropped 10 per cent. Assuming the rates were constant from 2003 to 2004, 10 per cent less people were seeing their doctors about depression. That is concerning to me," Katz said from Winnipeg.

The warning may even have deterred young adults from seeking therapy for depression. Records showed a 10 per cent drop in SSRI use in young adults (aged 19 to 24) - even though the health warning didn't pertain to use of the drugs by people in this age group.

Katz and his colleagues only studied data from Manitoba for the article. But they suggest what was seen there was probably also happening elsewhere, and even noted a study from the U.S. showed similar findings.

Their article, published Tuesday in the Canadian Medical Association Journal, is what is called an association study. It shows that the jump in completed suicides happened after the warning occurred and can be used to hypothesize the events are linked.

But this kind of study cannot prove the warning caused the increased suicides, the decreased SSRI use or the decline in doctor visits.

"We cannot say that the warnings or changes in antidepressant utilization or even (decline in) physician office visits have anything to do with the suicide rate. We can just document an association of those two things," Katz cautioned.

"This study raises many more questions than it provides answers. But they're important questions. And we need to figure out what's going on."

The key question the researchers wanted to highlight was whether warnings like the one issued by Health Canada in June 2004 could actually cause harm.

"(Drug) warnings are issued all the time," Katz said. "And there really is no mechanism to study what the impact of all these warnings is."

He said it would be understandable if parents had been frightened by the media coverage of the possible link between the drugs and suicidal thoughts in some children and teens who had used them.

"Parents are already anxious bringing their kids in when they're having these kinds of difficulties," Katz said.

Dr. Muhammad Mamdani, an expert in pharmacology, agreed that is what the figures seem to show.

"It actually suggests that well, you know, maybe people get nervous. They stop using their antidepressants. They stop going to the physician for depression and you see more suicides. That's what the study would suggest," said Mamdani, who is director of the Applied Health Research Centre at St. Michael's Hospital's Li Ka Shing Knowledge Institute in Toronto.

But Mamdani said there are caveats. The numbers of suicides were small - 99 over 11 years of study - and the two-year followup period was short.

"I still think we need a little bit more data and a little bit more followup to really stand up and say: 'Oh my God, I think there's something really major going on here,"' he said.

"It's certainly indicative. But not conclusive at this point."

Katz and his colleagues agreed their work had those limitations. But they suggested the way health warnings are conveyed to the public needs to be refined, so that people can better weigh the risks and benefits of taking medications that are linked to serious side effects.

For example, in this case the warning that the antidepressant drugs might carry a risk for children wasn't meant to suggest children suffering from depression shouldn't get medical care, he said.

"That's part of what our concern was, was that it was a very black and white message. And this isn't a black or white issue. It's a complicated issue. We're saying black probably wasn't the right representation, but white wouldn't be either."