When it comes to diagnosing who might be at an elevated risk of committing suicide, behavioral health practitioners have to hope patients having thoughts of taking their lives will confide in them.
Much of the time, however, that doesn't happen.
So some other way of screening people for suicide potential could prove a boon to the mental health profession. Researchers at the Indiana University School of Medicine have reported finding biological markers in the blood that appear to be associated with elevated suicide risk.
Writing in the Aug. 20 issue of the journal Molecular Psychiatry, the IU team, headed by Alexander Niculescu III, associate professor of psychiatry and medical neuroscience, report on a study that focused on a group of men with bipolar disorder for three years.
In addition to conducting psychiatric interviews with the test subjects, the researchers collected blood samples from the men every three to six months.
They then conducted numerous blood analyses on subjects in the study who began reporting they were having suicidal thoughts after initially having no self-destructive ideas.
After finding difference in gene expression between the low and high suicidal-thought states, Niculescu and his colleagues subjected those findings to a system of genetic and genomic analysis called Convergent Functional Genomics.
Starting in 1999, Niculescu and colleagues began developing CFG, a technique for prioritizing genes and biomarkers suspected of playing a role in complex psychiatric and medical disorders.
CFG is based on link analysis, a technique used in, among other applications, Web searches.
In this case, CFG identified a marker associated with a gene known as SAT1 and other biomarkers they believe provide a strong signal of suicide risk.
To test this idea, they analyzed blood samples of suicide victims they got from the coroner's office in Marion County, Ind. They found some of the candidates' suicide-risk markers were significantly elevated in the samples.
Niculescu and his colleagues are confident they are onto something but are not totally satisfied. One potential red flag is that all the test subjects were men. "There could be gender differences" in the relationships between the suspected biomarkers and suicide risk.
For now, Niculescu is willing to say, "These seem to be good markers for suicidal behavior in males who have bipolar mood disorders, or males in the general population who commit impulsive violent suicide."
Moving forward, the IU researchers want to conduct studies that match the biomarker data with clinical and socio-demographic risk factors to see how this works in predicting suicide risk.
"Over a million people each year worldwide die from suicide and this is a preventable tragedy," Niculescu said, who is associate professor of psychiatry and medical neuroscience at the IU School of Medicine, and attending psychiatrist and research and development investigator at the Richard L. Roudebush Veterans Affairs Medical Center, in Indianapolis.
In addition to IU and the V.A., Niculescu's collaborators came from the Scripps Research Institute.
The study was funded by a National Institutes of Health Directors' New Innovator Award and a Veterans Affairs Merit Award.