Scientists may be on their way to developing a blood test that could help identify people at a higher risk of committing suicide, according to a new study from the Indiana University School of Medicine.
A team of researchers studied the activity of certain genes by measuring how much RNA they produced. They found high levels of six types of RNA molecules, or biomarkers, in the bloodstreams of bipolar disorder patients who reported having suicidal thoughts, as well as in a group of people who had actually committed suicide. Blood tests could help psychiatrists identify those more likely to kill themselves.
During the course of three years, researchers followed a group of bipolar patients, and conducted a series blood tests and interviews to find if there was any biological indicator of suicide risk. They found that when the patients reported having "high" levels of suicidal thoughts, they also had high levels of the six biomarkers, with the strongest being the gene SAT1. To confirm that the same was true for people who had actually committed suicide, the researchers analyzed blood samples from nine deceased subjects, who had committed suicide by hanging themselves, shooting themselves or slitting their wrists, and found similar results.
Not only could the blood test provide an early warning of suicide risk, but it would also be useful because people who have suicidal thoughts, unlike those with chest pains or severe headaches, do not always reveal their symptoms to their doctors.
"There are people who will not reveal they are having suicidal thoughts when you ask them, who then commit it and there's nothing you can do about it," said lead researcher Alexander Niculescu, in a statement. "We need better ways to identify, intervene and prevent these tragic cases."
Worldwide, more than 1 million people die from suicide annually. In the United States alone, there are more than 38,000 suicide deaths each year, according to the Centers for Disease Control and Prevention. That works out to about one death every 14 minutes.
Niculescu, an associate professor of psychiatry and medical neuroscience at the medical school, told U.S. News that although the test subjects were all male and that there could be gender differences, a blood test appears to be a good indicator of impulsive suicidal behavior.
"Suicide is complex," he said. "Not everyone who has high levels of these biomarkers will go on and commit suicide. It has to be taken in context with other clinical and sociodemographic risk factors, like anxiety, mood, stress and family history."
Niculescu says some results of the study could also help predict long-term risk for suicide. The researchers compared their results with the blood tests and medical records of other patients, and found that the biomarkers were correlated with past and present suicide-related hospitalizations. He says the blood tests could be used with psychiatric patients, or could even help identify someone at risk for suicide at a routine primary care visit.
"There would be a chance to intervene early on and take measures to address other factors, like stress or anxiety, that could contribute to suicide risk," Niculescu says. "It might help prevent such a tragic outcome."