Abstract
Objective: Mild traumatic brain injury (mTBI) accounts for more than 75% of traumatic brain injuries every year. This study examines the temporal association between non-blast mTBI and the onset of neurologic sequelae to illuminate risks of post-concussive syndrome, epilepsy and chronic pain.
Methods: A large historical prospective study was conducted utilizing electronically-recorded demographic, medical and military-specific data for over half a million active duty US Air Force Airmen. This study utilized diagnostic codes to identify mTBI exposures, two control groups and three post-mTBI time periods. Adjusted hazard ratios (HRs) were calculated using Cox proportional hazards modelling.
Results: HRs were higher when mTBI exposed Airmen were compared with the full cohort and lower when compared with the other injured group. When compared to the other injured group, mTBI was positively associated with epilepsy/recurrent seizure outcomes, post-concussive syndrome and pain disorders. HRs tended to be highest within the first 30 days and decreased over time.
Conclusions: Findings support that mTBI may have a prolonged neurological impact. Findings are also likely generalizable to young adult populations with exposure to non-blast related mTBI, including civilians, as those included in this study were young adults with a high prevalence of recreational/sports and motor vehicle injuries.
Acknowledgements
The authors thank Eric Master and Chuck Goodyear of Infoscitex Corporation for their support in database development and graphical interpretations.
Declaration of interest
This study was conducted in accordance with all applicable federal regulations governing the protection of human subjects in research as approved by Air Force Research Laboratory/Wright Site Institutional Review Board (Protocol F-WR-2009-0066-H). This study was funded by the Defense Center of Excellence for Psychological Health and Traumatic Brain Injury. The statements herein do not necessarily reflect the opinions of the institutions represented by the authors. All authors made significant contributions to this study. The authors report no conflicts of interest.