Multiple traumatic brain injury and concussive symptoms among deployed military personnel

To identify if concussive symptoms occur with greater frequency among military personnel with multiple lifetime TBIs and if a history of TBI increases risk for subsequent TBI.

One hundred and sixty-one military personnel referred to a TBI clinic for evaluation and treatment of suspected head injury at a military clinic in Iraq.

Military patients completed standardized self-report measures of concussion, depression and post-traumatic stress symptoms; clinical interview; and physical examination. Group comparisons were made according to number of lifetime TBIs and logistic regression was utilized to determine the association of past TBIs on current TBI.

Patients with one or more previous TBIs were more likely to report concussion symptoms immediately following a recent injury and during the evaluation. Although differences between single and multiple TBI groups were observed, these did not reach the level of statistical significance. A history of any TBI increased the likelihood of current TBI diagnosis, but this relationship was no longer significant when adjusting for injury mechanism, depression and post-traumatic stress symptoms.

Among deployed military personnel, the relationship of previous TBI with recent TBI and concussive symptoms may be largely explained by the presence of psychological symptoms.