Background: Iraq and Afghanistan war veterans are returning from combat having sustained traumatic brain injury, most commonly mild traumatic brain injury (mTBI), and experiencing posttraumatic stress disorder (PTSD). Clinical guidelines for mTBI and PTSD do not focus on the co-occurrence of these conditions (mTBI/PTSD). A synthesis of the evidence on prevalence, diagnostic accuracy, and treatment effectiveness for mTBI/PTSD would be of use to clinicians, researchers, and policymakers.
Methods: We conducted a systematic review of studies identified through PubMed, PsycINFO, REHABDATA, Cochrane Library, pearling, and expert recommendations. Peer-reviewed English language studies published between 1980 and June, 2009 were included if they reported frequencies of traumatic brain injury and PTSD, or diagnostic accuracy or treatment effectiveness specific to mTBI/PTSD.
Results: Thirty-four studies met inclusion criteria. None evaluated diagnostic accuracy or treatment effectiveness. Studies varied considerably in design. Frequency of mTBI/PTSD ranged from 0% to 89%. However, in 3 large studies evaluating Iraq and Afghanistan war veterans, frequencies of probable mTBI/PTSD were from 5% to 7%; among those with probable mTBI, frequencies of probable PTSD were from 33% to 39%.
Discussion: The wide range of mTBI/PTSD frequency levels was likely due to variation across study parameters, including aims and assessment methods. Studies using consistent, validated methods to define and measure mTBI history and PTSD are needed.