A simple and quick blood test that could indicate that a person may exhibit a predisposition to suicide could serve as a future prevention tool, researchers say.
The blood test could reveal the presence of a genetic indicator that can reveal someone's susceptibility to the consequences of anxiety and stress and a resultant risk of possible suicidal thoughts, behaviors or attempts, researchers at the Johns Hopkins University School of Medicine say.
In The American Journal of Psychiatry, they report their identification of a gene dubbed SKA2, thought to be involved in regulating the brain's response to stress and releasing cortisol, a stress hormone, in the body.
"This [hormone] is important," says study lead Zachary Kaminsky, because it's the response that tells us to "move out of the way of traffic, for example."
In most people, when a danger or threat has passed, a normally functioning SKA2 gene help shut down the no longer needed cortisol secretion.
However, in individuals who have committed suicide or attempted it, there is less than the expected SKA2 gene expression in the brain region involved in inhibiting negative emotions and mediating impulsive behavior, researchers say.
That's the result of a mutation known as DNA methylation that suppresses the gene's normal expression, they say.
"We think this [SKA2 methylation] is causing a failure of the brain to shut down the stress response," Kaminsky says.
That failure can change a normal, temporary reaction to stressful situations in life into a lingering risk of suicidal thoughts or behaviors, the researchers say.
The mutation can be picked up by a blood test, they say; in a study experiment on 325 participants, blood test results where sufficient to identify to an accuracy level of 80 percent which of them were experiencing suicidal thoughts or had at some past time attempted suicide.
"With a test like ours, we may be able to stem suicide rates by identifying those people and intervening early enough to head off a catastrophe," Kaminsky says.
Such a test could have particularly beneficial applications in the military, which suffers a significant level of suicides that has increased 27.3 percent in the last two years.
A blood test to predict suicide risk in military members could allow those showing the highest risk to receive help and monitoring when they return from deployment, Kaminsky's research team said.
Those at most risk, once identified, could have their access to any lethal means restricted while proactive treatment is beginning, they said.
