Every 40 seconds there is a suicide somewhere in the world.
New research reveals how blood tests combined with questionnaires can accurately measure the risk of suicide in women. The results corroborate previous research that found the tools can predict suicide in men.
The study also found women and men have different reasons for taking their lives.
Data has already shown women are three times more likely to attempt suicide than men, though men are more than three times as likely to succeed due to their use of more violent means, usually guns. (Females more often use pills.)
The new findings suggest women are more likely to attempt suicide if they feel socially isolated, while men try to kill themselves when they're under too much pressure.
The results also demonstrate why gender is a factor when recommending therapy, the study's lead author, Alexander B. Niculescu III, says. For example, women may benefit from support groups, whereas men might improve with meditation or relaxation techniques.
The study, from the Indiana University School of Medicine, was published online in the journal Molecular Psychiatry.
Researchers followed 51 female patients who had been diagnosed with mental health issues such as bipolar disorder, depression and schizophrenia, in order to track their risk for suicide.
For four years, both their mental health status and their blood were tested every three to six months. The goal was to see if combining mental self-evaluations with biological tests could accurately predict whether someone would attempt to take her own life.
The goal of the blood tests was to offer a more objective measure of suicide risk, one that didn't rely on patients telling the truth.
“The problem with people who are really serious about committing suicide is they do not share that [information] with their clinicians, or with their loved ones, or friends, for fear of being hospitalized or stopped from committing the act,” said Niculescu, a professor of psychiatry and medical neuroscience at Indiana University.
So researchers looked for molecular changes or chemicals in the blood, called RNA biomarkers, that appear to correlate with suicidal thoughts.
In other words, some chemicals in the blood change when you're thinking about ending your life.
"We were able to identify markers that changed between a state where [the patients] had absolutely no suicidal ideation and a state where they had very high suicidal ideation," Niculescu says. “Just like you would look at high cholesterol, or inflammatory markers in cardiovascular diseases, here you would have these markers that would alert you that somebody is at high risk."
Evaluating Mental Health
In concert with the blood tests, researchers used two apps to evaluate the mental health of study participants.
The first app tracked mood and anxiety. Throughout the day, patients responded to simple prompts asking about their mood at a particular time.
"[The app] is kind of like an odometer on a car,” said Niculescu. “It says, ‘Compared to the lowest your mood has ever been and the highest it’s ever been, where are you at this moment in time.’”
The second app measured suicidal risk by asking questions in 22 different areas, including life history, psychiatric history, addictions, recent deaths, chronic pain and current sources of stress. When a patient completed the questionnaire, a risk assessment was generated. Niculescu likens it to a FICO mortgage score that instead of measuring credit risk evaluates a tendency toward suicide.
"We looked at how the suicide predicter app, the mood and anxiety scores and the biomarkers combined can predict suicide. And there's synergy," says Niculescu. "The biomarkers by themselves are predictive. The apps by themselves are predictive. And when you combine them, you get an even better prediction."
Through this combination the researchers were able to predict suicidal risk with more than 80 percent accuracy. Niculescu says he was thrilled blood tests might offer psychiatrists a concrete tool to predict behavior.
“You can make psychiatry just like every other medical field where you use objective tests to support diagnoses!" he exclaimed. “You can give people the best care in a tailored fashion based on their gender, based on their diagnoses and based on their risk factors.”
During the four-year study, one participant committed suicide. And, when the analyses were completed, her risk prediction score was at the 100th percentile of all participants. Researchers hope earlier predictions can prevent future tragedies.
The study was limited to high-risk females with psychiatric diagnoses in a VA hospital, so researchers are not certain the combined tests will work to predict suicidal risk in a more general population.
"I suspect that our findings will be more generalizeable, but we do have a lot of work to do to establish levels in different populations by gender, by age, by diagnosis, by ethnicity and so on," says Niculescu.
He and his team have larger studies in the works, he said.