Long-term Mental Health Trajectories of Injured Military Servicemembers: Comparing Combat to Noncombat Related Injuries.

Abstract

We sought to quantify the impact of injury characteristics and setting on the development of mental health conditions, comparing combat to noncombat injury mechanisms. Due to advances in combat casualty care, military service-members 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 and 2011. Controls were servicemembers injured in a noncombat 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, depression, and anxiety) among combat-injured servicemembers were compared to controls. Risk factors for developing a new mental health condition after traumatic injury were evaluated using multivariable logistic regression that controlled for confounders. There were 3979 combat-injured servicemember and 3979 matched controls. The majority of combat injured servicemembers (n = 2524, 63%) were diagnosed with a new mental health condition during the course of follow-up, compared to 36% (n = 1415) 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) servicemem-bers were also at significantly greater risk. We found significantly higher rates of new mental health conditions among servicemembers injured in combat compared to service-members sustaining injuries in noncombat settings. This indicates that injury mechanism and environment are important drivers of mental health sequelae after trauma.