We sought to quantify the impact of injury characteristics and setting on the development of mental health conditions, comparing combat to non-combat injury mechanisms.
Summary Background Data:
Due to advances in combat casualty care, military servicemembers are surviving traumatic injuries at substantial rates. The nature and setting of traumatic injury may influence the development of subsequent mental health disorders more than clinical injury characteristics.
TRICARE claims data was used to identify servicemembers injured in combat between 2007–2011. Controls were servicemembers injured in a non-combat setting matched by age, sex, and injury severity. The rate of development, and time to diagnosis (in days [d]), of 3 common mental health conditions (post-traumatic stress disorder [PTSD], depression, and anxiety) among combat-injured servicemembers were compared to controls. Risk factors for developing a new mental health condition following traumatic injury were evaluated using multivariable logistic regression that controlled for confounders.
There were 3,979 combat-injured servicemember and 3,979 matched controls. The majority of combat injured servicemembers (n = 2,524, 63%) were diagnosed with a new mental health condition during the course of follow-up, compared to 36% (n = 1,415) of controls (p < 0.001). In the adjusted model, those with combat-related injury were significantly more likely to be diagnosed with a new mental health condition (Odds Ratio (OR): 3.18, [95% Confidence Interval (CI): 2.88–3.50]). Junior (OR: 3.33, 95%CI: 2.66–4.17) and senior enlisted (OR: 2.56, 95%CI 2.07–3.17) servicemembers were also at significantly greater risk.
We found significantly higher rates of new mental health conditions among servicemembers injured in combat compared to servicemembers sustaining injuries in non-combat settings. This indicates that injury mechanism and environment are important drivers of mental health sequelae following trauma.