Acute post-traumatic stress symptoms and age predict outcome in military blast concussion

Abstract

High rates of adverse outcomes have been reported following blast-related concussive traumatic brain injury in US military personnel, but the extent to which such adverse outcomes can be predicted acutely after injury is unknown. We performed a prospective, observational study of US military personnel with blast-related concussive traumatic brain injury (n = 38) and controls (n = 34) enrolled between March and September 2012. Importantly all subjects returned to duty and did not require evacuation. Subjects were evaluated acutely 0-7 days after injury at two sites in Afghanistan and again 6-12 months later in the United States. Acute assessments revealed heightened post-concussive, post-traumatic stress, and depressive symptoms along with worse cognitive performance in subjects with traumatic brain injury. At 6-12 months follow-up, 63% of subjects with traumatic brain injury and 20% of controls had moderate overall disability. Subjects with traumatic brain injury showed more severe neurobehavioural, post-traumatic stress and depression symptoms along with more frequent cognitive performance deficits and more substantial headache impairment than control subjects. Logistic regression modelling using only acute measures identified that a diagnosis of traumatic brain injury, older age, and more severe post-traumatic stress symptoms provided a good prediction of later adverse global outcomes (area under the receiver-operating characteristic curve = 0.84). Thus, US military personnel with concussive blast-related traumatic brain injury in Afghanistan who returned to duty still fared quite poorly on many clinical outcome measures 6-12 months after injury. Poor global outcome seems to be largely driven by psychological health measures, age, and traumatic brain injury status. The effects of early interventions and longer term implications of these findings are unknown.

Early Clinical Predictors of 5-Year Outcome After Concussive Blast Traumatic Brain Injury

“…9–12,29,30 The present study is the 5-year evaluation in a continued prospective, observational, longitudinal research study. We report the 5-year clinical outcomes compared with 1-year findings in the following participant groups: patients with concussive blast TBI and combat-deployed control individuals.…”

“…Inclusion criteria are reported elsewhere. 9,10,30 In brief, participants were service members deployed to combat from November 1, 2008, through July 1, 2013, for whom original enrollment was completed directly in Afghanistan 9,29 or after medical evacuation to Landstuhl Regional Medical Center in Landstuhl, Germany. 10–12,30 Diagnosis of head injury was determined by trained medical personnel working in the TBI clinics in Germany.…”

“…Although civilian studies 8 have reported poor outcomes on the Extended Glasgow Outcome Scale (GOS-E) in 22% to 33% of patients with mild TBI, reports of mild TBI sustained in combat have identified 62% to 96% with poor outcomes on the same measure. 9–12 …”

“…In contrast, our group was provided the unique opportunity to examine patients in the acute 9,29 to subacute 10–12,30 stage after combat-related concussive TBI with prospective follow-up to 1-year 9–12,30 and now 5-year evaluations. This longitudinal observation has allowed for a greater appreciation of functional postinjury trajectory and the effect on long-term outcome.…”

Discriminating military and civilian traumatic brain injuries

“…A means of assessing who is likely to respond to a particular type of treatment would be a valuable rehabilitative tool. A recent study showed that when comparing acute symptoms to chronic symptoms (postconcussion and mental health) after mTBI that chronic symptoms are a better predictor of outcome 6-12 months after injury (Mac Donald et al, 2015). This is not surprising; however, it underscores the need to discover variables with high predictive value of outcome after mTBI acutely.…”