About four percent of US teens surveyed admit to trying the "choking game" – a potentially deadly game of temporary strangulation.
Blood and oxygen
And new research suggests that kids who "play" the game alone are much more likely to harbour thoughts of suicide.
The so-called choking game is the practice of using hands, fingers or external wrapping materials – such as a belt, tie or noose – to apply strong pressure against the carotid arteries lining either side of the neck.
Located on the right and left side of the windpipe, these arteries are critical conveyors of blood and oxygen to the brain. By interrupting the usual blood flow, and then suddenly removing pressure to restore flow, individuals reportedly trigger a short-lived feeling of euphoria.
Read: The choking game
But, the practice carries a high risk for asphyxiation, loss of consciousness, and even death. And the risks grow when "players" act alone without anyone around to intervene and stop an out-of-control strangulation process, the study authors said.
"We know from earlier research that youth who engage in the choking game also report higher levels of suicidal thoughts than those who don't participate in the choking game at all," said study co-author Sarah Knipper.
"This new study tells us that within that group of kids, those who participate alone are even more likely to have suicidal thoughts," added Knipper. "[They're] five times more likely than those who participate in a group."
Knipper is a school health epidemiologist with the adolescent and school health programme in the Oregon Public Health Division of the Oregon Health Authority in Portland.
The study authors pointed to prior estimates suggesting that somewhere between five percent and 11 percent of American children have tried the choking game at least once. Fatality figures remain unclear, however, as related deaths are often lumped in as undefined suicides or accidents.
The new study looked at mental health data on roughly 21,000 students in grades eight and 11 in Oregon. The information was collected in 2011 and 2013 by the Oregon Healthy Teens Survey. Oregon is the only state that routinely monitors choking game behaviour in its surveys, the study authors said.
The researchers found that nearly four percent of both boys and girls said they had participated in a choking game at some point in their lives. Of these, about 18 percent said they had done so by themselves.
Read: Choking game common in kids
What's more, teens who had tried the practice alone were almost five times more likely to have thoughts of suicide than those who had done it in groups, and more than twice as likely to say they were in poor mental health overall.
Knipper said that "many parents are not aware of the choking game at all".
Sarah Feuerbacher, clinic director of the Southern Methodist University Centre for Family Counselling in Plano, Texas, stressed that parents should know that "children who participate in the 'choking game' aren't playing a game at all. They are engaging in self-harm."
Pain behind aggression
And, Feuerbacher added, "Even more challenging to take in [is that] children who are depressed are the ones who engage in self-harming behaviours."
Parents should try to offer "a safe, 'shame-free' time and place to talk to their child when the parent isn't a 'parent' but simply listens", she advised.
"The parent should be quiet, be patient, and really listen. They should make brief statements and wait for a response. They should look for pain behind aggression. They should show empathy and compassion, and they should convey admiration for the child," Feuerbacher suggested.
What's most important is to get your teen help from a trained mental health professional, Feuerbacher said. "There may be no second chances," she added.
Read: Psychotherapy leads to healthier stress hormone levels
George Holden, chair of Southern Methodist University's department of psychology in Dallas, also urges parental intervention.
"Once parents learn of [the choking game], they need to openly discuss it with their teenagers," he advised. "In fact, such a discussion could be a useful way to start a conversation about feelings of depression, low self-esteem, and other mental health problems."
As many as one in five teens experiences depression, and parents should reassure their child that their problems are both common and treatable, Holden said.
"Teens need to know that help is available for them from school counselors or psychologists," he said.
The study was published online in the journal Paediatrics.
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