UI researchers study genetic risks for suicide in people with bipolar disorder
In a new study from the University of Iowa and University of Utah, researchers found that people with bipolar disorder may be at a greater risk for suicide due to a genetic predisposition or diagnosis of PTSD.
July 20, 2021
A new study from the University of Iowa and University of Utah researchers shows that people with bipolar disorder who experience trauma may be at a greater risk for suicide. Their findings suggest that knowledge of a genetic predisposition to post-traumatic stress disorder (PTSD) could be an important factor in suicide prevention.
According to the American Foundation for Suicide Prevention, suicide is the 10th leading cause of death in the U.S., with over 40,000 Americans dying by suicide every year.
The research, which looked at unique risk factors for suicide death for people with bipolar disorder, was led by multiple researchers with connections to the UI, including Eric Monson, chief resident in psychiatry at the University of Utah and 2018 UI Carver College of Medicine graduate, Hilary Coon, a University of Utah psychiatry professor, and Virginia Willour, a UI psychiatry professor.
“Suicide isn’t due to just one thing — there are many factors that contribute to suicide risk and genetics is one of them,” Willour said. “We need to study it alongside and in collaboration with folks looking at the other factors as well.”
Monson said this study is one of the first that investigates risk factors specifically for suicide, not just attempts. The team looked at bipolar disorder because of the higher risk for suicide, which is 10 to 30 times higher than the general population, he said.
“Bipolar disorder is particularly interesting to us because it’s a disease that has a very high risk of suicide,” Monson said. “It also has a lower rate of attempt to death than a lot of other diagnoses do… a lot of people die without having a prior attempt.”
The study looked at suicide attempt versus suicide death, finding that people who attempt suicide are likely to be female, and people who die by suicide are likely to be male, Coon said.
“There are some pretty substantial differences between those who attempt versus people who go on to die by suicide,” Coon said. “We’re looking at this from a standpoint of what aspects in clinical history are important, what aspects from genetics are important, and the other aspects that are going to be important, like environmental factors.”
Within this study, they looked at the role of PTSD in bipolar disorder, Monson said. The data showed that people with bipolar disorder who died from suicide had a much higher rate of PTSD diagnoses than any other group, he said.
“People who have PTSD — more broadly, people who have experienced trauma — tend to have more severe disease, they tend to have more severe symptoms than other people, and they tend to be harder to treat with medications,” Monson said. “There has been evidence that these people are more likely to engage in suicidal behavior.”
Monson said people within this study had a genetic profile consistent with PTSD.
“Individuals who die by suicide have a genetic profile that is consistent with risk for developing PTSD,” Monson said. “They also had a greater rate of diagnosis of PTSD than those who attempted suicide and other groups in the study.”
While these results are promising for those who are most at-risk, there still isn’t a definitive answer to the complicated puzzle of preventing suicide, Monson said.
“There’s no genetic test that predicts or determines suicide,” Monson said. “These test results don’t offer something that is predictive in nature — they offer some idea of where the risk is.”
This study was funded by a grant from the American Foundation for Suicide Prevention and looked at unique samples from the University of Utah public database, which collects data on individuals who died by suicide over a number of decades in the state, Monson said.
The researchers also used data from the National Institute of Mental Health (NIMH) Genetics Initiative. Monson said they compared samples from those with bipolar disorder who died from suicide with samples of people who had a history of suicide attempts.
Willour said it’s important to identify these potential risk factors to help prevent suicide, especially in people who are most at-risk and need better access to mental health resources.
“DNA is not destiny — there are a number of things that you can do today to decrease risk. One of them is to tell somebody — tell a doctor, tell somebody you trust that you’re struggling,” Willour said. “Even if you have this genetic risk, suicide is preventable.”
Because of the findings of the study, the team emphasized the importance of universal screening, Monson said.
“When people are in health care settings, they should be being asked whether they have thoughts of taking their own life, whether they are feeling safe, whether they are being compliant with their treatment, and whether they have depression that’s not being treated,” Monson said. “These risk factors are things that could be picked up on if people are being asked these important questions by their doctors.”
Monson said these findings and looking for ways to prevent suicide is important to the team.
“This is a really critical thing that has touched so many lives and so many people,” Monson said. “This is not just a job — it’s a mission — and it’s really important to us.”
[If you are having thoughts of suicide, call the National Suicide Prevention Lifeline at 1-800-273-8255 (TALK) or go to SpeakingOfSuicide.com/resources for a list of additional resources.]