WEDNESDAY, July 26, 2017 (HealthDay News) -- Troubling new study findings suggest that U.S. Army soldiers are more likely to try to kill themselves if another member of their unit has attempted suicide in the previous year.
In fact, the researchers linked almost 20 percent of such suicide attempts to recent attempts by others in their units.
It's not clear if the findings reflect a contagion-like effect, high levels of stress inside specific units or something else altogether, the investigators noted.
Whatever the case, "when a suicide attempt occurs in a unit, there is increased risk of another suicide attempt," said study author Dr. Robert Ursano. He is a professor of psychiatry and neuroscience at the Uniformed Services University, in Bethesda, Md. "Being alert to clusters of suicide attempts may offer new avenues for intervention to decrease suicide attempt rates."
Suicides among active members of the military are rare, but research suggests the rate doubled between 2001 and 2011, a period in which the Iraq and Afghanistan wars began. Statistics suggest the Army has the highest suicide rate among the U.S. military branches.
For the new study, researchers tracked 9,512 suicide attempts among active-duty enlisted Army soldiers from 2004 through 2009. The findings showed that most who tried to kill themselves were male (86 percent), younger than 30 (68 percent) and white (60 percent).
After adjusting their statistics so they wouldn't be thrown off by various factors, the investigators found that soldiers faced 1.4 times the odds of attempting suicide if someone in their unit had tried to kill themselves in the past year.
Soldiers in units with five or more suicide attempts over the past year had 2.3 times the odds of trying to kill themselves. (Army units can include as many as 600 soldiers.)
The researchers also estimated that 18 percent of suicide attempts are linked in some way to the previous attempts, although they couldn't prove that the earlier attempts caused the later attempts.
Alan Peterson, a professor of psychiatry at the University of Texas Health Science Center at San Antonio, said it's possible that conditions within units could be the cause of higher rates of suicide attempts.
"Contagion is also a likely possibility," Peterson said. "It could also be that combat units are collectively exposed to similar combat-related traumatic events that universally increase the overall risk of future suicides."
What should be done?
According to Kipling Bohnert, an assistant professor of psychiatry with the University of Michigan, "It may be important for military suicide prevention efforts to specifically target units with a history of suicide attempts to prevent future attempts."
Dr. Charles Hoge, who co-wrote a commentary accompanying the study, said mental health problems are the biggest risk factor behind suicidal behavior.
"Sometimes these problems go unrecognized and untreated, and for this reason some of the most important ongoing efforts focus on reducing stigma and ensuring optimal access to care," said Hoge. He is a senior scientist with the Walter Reed Army Institute of Research, in Silver Spring, Md.
Hoge noted that the study period only lasted until 2009, and doesn't reflect major changes that have been made in how the Army deals with the mental health of U.S. soldiers.
"Since 2010, the U.S. Army has been extensively transforming the structure of mental health services," he explained.
"This transformation includes population-wide screening for mental health problems; increases in mental health-care professionals; standardization of services; routine clinical outcome measures; and restructuring of care delivery to improve access, reduce stigma, and enhance coordination of services and communication with unit leaders," Hoge added.
The study was published online July 26 in JAMA Psychiatry.
For more about suicide risk factors, visit the National Suicide Prevention Lifeline.