Correlates of Depression in US Military Service Members With a History of Mild Traumatic Brain Injury

Objectives Post-traumatic stress disorder (PTSD) and traumatic brain injury (TBI) are identified as signature injuries of the Wars in Iraq and Afghanistan. Statistics have confirmed a high incidence of PTSD among military personnel with mild TBI (mTBI) who served in these conflicts. Although receiving less attention, individuals with a history of mTBI are also at increased risk for depressive disorders. This study examines the incidence and correlates of depression in service members with a history of mTBI received an average of 4-1/2 years prior to evaluation. Methods Retrospective analysis of 184 service members with a history of mTBI extracted from a data repository maintained at a military medical center. Results One-third of the sample (34.2%) was clinically diagnosed with a depressive disorder in the month preceding evaluation. Of those with depression, 81% (51 of 63) were also diagnosed with PTSD. Proportionately more women than men had depression. Depression was more common among those who were undergoing a Military Evaluation Board and those who served in more than three combat deployments. Conclusions Results confirm chronically elevated the rates of depressive disorders and PTSD comorbidity among service members with a history of mTBI. Depression screening and treatment within the Military Health System should remain a priority for service members reporting a remote history of mTBI. Individuals with chronic PTSD, women, service members undergoing MEB and those who served in greater than three combat deployments are at particular risk.