New research has identified brain circuitry differences that might be associated with suicidal behavior in individuals with mood disorders.
The study provides a promising lead toward tools that can predict which individuals are at the highest risk for suicide, according to researchers at the University of Utah Health and the University of Illinois at Chicago.
Suicide rates are rising steadily among young adults, especially those with mood disorders, such as depression. More than half of individuals who commit suicide saw a health professional within the past 30 days, but they did not necessarily seek care for mood problems, the researchers note.
“At present, we have very few tools to identify individuals who may be at high risk for suicide-related behavior,” said Dr. Scott Langenecker, a professor of psychiatry at the University of Utah Health and senior author on the study. “Right now, we go on self-report and clinician judgment. Those are good, but they’re not great.”
Previous studies identified brain circuits associated with mood disorders: The cognitive control network (CCN), which is involved in executive function, problem-solving and impulsivity; the salience and emotional network (SEN), which is involved in emotion processing and regulation; and the default mode network (DMN), which is active when individuals are engaged in self-focused thought.
However, these studies focused primarily on depression, according to the researchers.
“This is one of the first studies to try to understand brain mechanisms that may be relevant to suicide risk,” said Dr. Jonathan Stange, an assistant professor of psychiatry at the University of Illinois at Chicago and first author on the study.
The study used resting-state functional MRI (fMRI), which captured brain images while participants were rested and calm, to assess the connectivity of these circuits in 212 young adults at the University of Illinois at Chicago and the University of Michigan.
“For risk factors involved in suicide, the tasks we have to measure are pretty nonspecific and inexact,” Langenecker said. “If we go to the level of the resting-state networks, we’re actually asking the brain to tell us which brain networks and connections are most relevant.”
The study included individuals with mood disorders and a history of suicide attempts, those with mood disorders and a history of suicidal thoughts, those with mood disorders and no history of suicidal behavior or thoughts, and healthy controls. All study participants with mood disorders were in remission, the researchers noted.
Compared with other study participants — even those with mood disorders and a history of suicidal thoughts — people with a history of suicide attempts showed less connectivity in the CCN and between the CCN and DMN, neural circuitry associated with cognitive control and impulsivity, according to the study’s findings.
These differences could present a target for treatment, according to the researchers.
“If we could figure out how to improve connectivity within this brain circuit, we might be able to reduce suicide risk in the future,” Stange said.
Stange and Langenecker emphasize the research is still in its early stages. This was a small study, with only 18 participants with mood disorders and a history of suicide attempts. It will have to be replicated in a larger number of participants, they said.
In addition, the researchers note it is not yet clear whether individuals with mood disorders and at risk for suicide have a different disease from those without such risk, or whether all individuals with mood disorders are at varying degrees of risk for suicide.
The study was published in Psychological Medicine.