Relationship of screen-based symptoms for mild traumatic brain injury and mental health problems in Iraq and Afghanistan veterans: Distinct or overlapping symptoms?

This study used factor analytic techniques to differentiate distinct from overlapping screen-based symptoms of traumatic brain injury (TBI), posttraumatic stress disorder (PTSD), and depression in Iraq and Afghanistan veterans. These symptoms were derived from screen results of 1,549 veterans undergoing Department of Veterans Affairs postdeployment screening between April 2007 and January 2010. Veterans with positive TBI screens were approximately twice as likely to also screen positive for depression and PTSD (adjusted relative risks = 1.9 and 2.1, respectively). Irritability was a shared symptom between TBI and PTSD, and emotional numbing was a shared symptom between PTSD and depression. Symptoms unique to TBI included dizziness, headaches, memory problems, and light sensitivity. Four separate constructs emerged: TBI, PTSD, depression, and a fourth construct consisting of hypervigilance and sleep problems. These findings illuminate areas of overlap between TBI and common postdeployment mental health problems. Discriminating symptoms of TBI from mental health problems may facilitate diagnosis, triage to specialty care, and targeted symptom management. The emergence of a fourth factor consisting of sleep problems and hypervigilance highlights the need to attend to specific symptoms in the postdeployment screening process.