In 2015, five girls out of every 100,000 between the ages of 15 and 19 committed suicide in the United States.
The rate is double what it was in 2007, and the highest in 40 years for that age group, according to newly released data from the Centers for Disease Control (CDC) and Prevention.
The reasons for the rise are complex - researchers point, in part, to teens' increasing access to social media, an ongoing lack of mental-health resources and a stigma against suicidal behavior - and not entirely understood. But for suicide-prevention advocates and researchers, the announcement about the 40-year high wasn't a shock.
"It doesn't surprise me that it has come to this spot," said James Mazza, a University of Washington professor in the College of Education's School Psychology program.
A CDC analysis found that 524 females between 15 and 19 died by suicide in 2015 in the U.S. The rate for females is still much lower than the suicide rate for males - in 2015, 1,537 males between 15 and 19 committed suicide.
But the rising rate among females is troubling, suicide-prevention advocates said, and signals a need for parents and educators to address the stigma of suicidal thoughts and behavior.
And while he can't point to one specific reason for suicidal behavior, Mazza said that social media have likely exacerbated the problems teens face, like the pressure to fit in.
"We have kids who have access to social media 24/7 that's providing extra opportunities, especially with teen girls, to make comparisons among themselves," he said. "There's a hypervigilance of how they fit in. They don't see themselves as like the other girls they see on Facebook and Snapchat. We also need to be worried about boys, as their suicide rates are still higher than girls, and they face increased pressure and scrutiny as well."
More girls tend to have internalized disorders - like anxiety, depression or anorexia - that are difficult for parents or school staff to see if they don't know the signs. A study published in the journal Pediatrics last year found that about 17 percent of teen girls have experienced a major depressive episode in the past year, compared with 6 percent of teen boys. Males have higher rates of ADHD, substance abuse or anti-social behaviors that are easier to spot, so they might have a better chance of receiving help, Mazza said.
And while more teen boys died by suicide, more girls attempt it, noted Aimee Chou, spokeswoman for Forefront, a suicide-prevention center at the UW. Teen boys are more likely to use firearms than females, who tend to use less lethal means, like cutting or taking pills.
In King County, 51 girls between ages 11 and 18 committed suicide since 2000, and 10 used a firearm, according to data from the King County Medical Examiner's Office. In that same period, a third of the 105 boys who committed suicide did so by using a firearm.
Across the state, 26 percent of sophomore girls who answered the state's 2016 Health Youth Survey reported thinking about suicide, and 13 percent said they had attempted it.
Without more intervention, Mazza thinks the numbers will continue to rise.
"I've been writing about this for 20 years," he said, "and I thought the rates were high 20 years ago."
Signs of potential suicidal behavior include talking about dying, changes in personality, behavior, sleep patterns or eating habits, and a fear of losing control.
Information, support and referrals are available by calling the Suicide Prevention Lifeline at 800-273-8255 (TALK) or contacting TeenLink at 866-833-6546. If a teen is in an emergency, call 911 or go immediately to the nearest hospital emergency room.
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