Military veterans with a history of traumatic brain injury (TBI) are more than twice as likely to die of suicide compared to veterans without such a diagnosis, reveals a study. 

Researchers reviewed electronic medical records of over 1.4 million military veterans who received care between October 1, 2005, and September 30, 2015. Combining these records with National Death Index data, they evaluated the severity of TBI, and diagnoses of psychiatric and other medical conditions. After adjusting for psychiatric diagnoses, such as depression, the researchers found that those with moderate or severe TBI were 2.45 times as likely to die by suicide compared to those without a TBI diagnosis. 

Additionally, among suicide decedents, they report that the odds of using firearms as a means of suicide was significantly increased for those with moderate or severe TBI as compared to those without a history of TBI. "Together, these findings underscore the importance of understanding Veterans' lifetime history of TBI to prevent future deaths by suicide, and support the implementation of screening initiatives for lifetime history of TBI among all individuals utilizing the VHA," the researchers wrote in the journal of Head Trauma Rehabilitation. 

Moreover, the findings supported research regarding lethal means safety among those with moderate to severe TBI. 
During the period of time the researchers studied, the rate of suicide was 86 per 100,000 person years for those with TBI compared with 37 per 100,000 person years for those without TBI. Of those in the sample who died by suicide, 68 per cent used firearms. Veterans with moderate or severe TBIs had the highest proportion of suicides by firearms at 78 per cent.