Military-Related TBI Increases Likelihood of Mental Health Conditions

The rates of new-onset mental health conditions are higher among soldiers who experience military-related traumatic brain injury (TBI), according to study findings published in JAMA Network Open. 

The relationship between TBI and other health conditions remains unclear, particularly mental health conditions. Previous studies in this area have not focused on the timing of TBI in relation to the development of mental health diagnoses. 

Researchers conducted a retrospective cohort study to determine differences in the rate of new-onset mental health conditions among soldiers with and without military-related TBI. The association between TBI and suicide was also assessed. 

Data was collected from the Substance Use and Psychological Injury Combat Study (SUPIC) database, the Department of Defense, and the National Death Index records. A total of 860,892 soldiers were included in the study, with 320,539 soldiers (37.2%) aged 18 to 24 years at the end of index deployment. Of these participants, 766,454 (89.0%) were men and 108,785 (12.6%) had at least 1 TBI.

Of the participants with TBI history, 458 (0.4%) died by suicide, compared with 2237 soldiers (0.3%) without a TBI history.

Mental health diagnoses were higher among soldiers with a TBI history compared with those without TBI. In addition, among patients with TBI compared with those without a history of TBI, there were higher increases in mood diagnoses (67.7% vs 37.5%) and substance use (100% vs 14.5%, respectively). The researchers note that these disparities are largely due to the increased rates of new-onset mental health diagnoses for patients with TBI.

Compared with soldiers without TBI, the time-to-suicide among soldiers with a TBI history was 21.3% faster (deceleration factor, 0.787; 95% CI, 0.715-0.866). 

For patients with 2 or more mental health diagnoses, the direct effect estimates of TBI on time-to-suicide for soldiers with TBI was 8.5% faster (deceleration factor, 0.915; 95% CI, 0.829-1.010) than those without a TBI.

The adjusted model reported a time-to-suicide of soldiers with TBI of 16.7% faster (deceleration factor, 0.833; 95% CI, 0.756-0.918) compared to those without TBI.

“These findings support adopting methodological strategies aimed at evaluating risk over an individual’s lifetime, with a focus on how events and conditions accumulate both proximally and distally,” the researchers wrote. They concluded, “In addition, efforts to identify evidence-based interventions that address mechanisms associated with frequently co-occurring conditions (ie, TBI and mental health disorders) are needed.”

Study limitations are incomplete data, difficulties with differential diagnoses and overlapping symptoms, and confounding factors. 

Disclosure: Some study authors declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of authors’ disclosures.

This article originally appeared on Neurology Advisor