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Many studies have evaluated the influence of mild traumatic brain injury (mTBI) on neuropsychological test performance and on report of postconcussive symptoms. However, most studies that examine postconcussion syndrome (PCS) do not address the issue of “polytrauma,” which is common in military mTBI. This study investigated simultaneously demographic, injury-related, and psychiatric symptom predictors of PCS report in a veteran, polytrauma sample. In prediction of overall report of PCS symptoms with demographic, traumatic brain injury, psychiatric and sleep variables, 60% of the variance was explained. Semipartial correlations revealed that post-traumatic stress disorder uniquely explained 7% of the variance, depression 2%, and sleep dissatisfaction 3%; injury and demographic characteristics accounted for no unique variance. In all 5 hierarchical multiple regressions (prediction of total Neurobehavioral Symptom Inventory score and 4 individual factor scores), the total models were significant ( p < 0.001). Accurate diagnosis and treatment necessitates an integrative analysis of PCS, psychiatric, behavioral, and health symptom report in addition to neuropsychological functioning in the polytrauma population. This study demonstrated that emotional distress was uniquely predictive of total report of PCS and that no injury-related characteristics were predictive. This is of particular relevance in a Veteran population given the high rates of both mTBI and psychiatric disturbance. INTRODUCTION Numerous studies have evaluated the influence of mild traumatic brain injury (mTBI) on neuropsychological test performance and on report of postconcussive symptoms. However, most studies that examine postconcussive symptoms do not address the issue of “polytrauma,” which is often the mechanism that causes military mTBI. The Veterans Health Administration defines polytrauma as “two or more injuries to physical regions or organ systems, one of which may be life threatening, resulting in physical, cognitive, psychological, or psychosocial impairments and functional disability. ” Polytrauma and the common experience of psychiatric distress are likely to be extremely important in predicting patient prognosis and making symptom attributions. Accurate diagnosis necessitates an integrative analysis of postconcussive syndrome (PCS), psychiatric and behavioral health symptoms, and neuropsychological functioning within a polytrauma setting. Traumatic Brain Injury and PCS: Definitions and Symptom Expectation Traumatic brain injury (TBI) results from an external force acting on the brain and may involve any of a number of types of intracranial damage. TBI is typically rated as mild, moderate, or severe. At least 75% to 90% of all brain injuries are classified as mild. The present study focuses on mTBI, characterized by confusion, disorientation, or loss of consciousness (LOC) for less than 30 minutes. Multiple studies have demonstrated differences in test performance between those with mTBI and those with moderate to severe TBI, with mTBI patients evidencing little impairment. Even in populations that have sustained multiple mTBIs, lasting impairments are infrequent. Typical residual symptoms associated with mTBI may include headache, dizziness, irritability or outbursts of anger, double vision, ringing in the ears, decreased concentration, and forgetfulness. Symptoms usually last only the first few days to weeks after the injury and resolve within 1 to 3 months postinjury. Persistence of these symptoms for greater than 1 month is defined as PCS. Multiple studies have demonstrated that PCS symptoms are not exclusive to mTBI and may instead reflect post-traumatic emotional sequelae or other nonspecific factors. A prospective analysis demonstrated that continuation of PCS symptoms over time is maintained by psychological distress including depression, anxiety, pain, and post-traumatic stress but not by injury severity. PCS may also be propagated by symptom expectation. Gunstad and Suhr found that when undergraduate students were asked to predict the symptoms they would expect to experience after an orthopedic injury, head injury, posttraumatic stress, or depression, participants expected higher levels of symptoms related to head injury, post-traumatic stress, and depression, as compared to an orthopedic injury. Interestingly, subjects asked to respond as if they had experienced a concussion reported fewer cognitive and affective symptoms than the other groups. This supports the idea that symptom expectation may be part of the etiology of PCS or at least contributes to symptom maintenance. Expectancy effects also have a significant bearing on a patient’s prognosis. Telling veterans that they are “brain *VA Ann Arbor Healthcare System, 2215 Fuller Drive, Ann Arbor, MI 48105. †Department of Physical Medicine and Rehabilitation, University of Michigan Health System, E. Eisenhower Pkwy, Ann Arbor, MI 48108. ‡Department of Psychiatry, University of Michigan Health System, 1500 E. Medical Center Drive, Ann Arbor, MI 48109. doi: 10.7205/MILMED-D-13-00282 MILITARY MEDICINE, Vol. 179, August 2014 856 D ow naded rom http/academ ic.p.com /m ilm ed/article-ab/179/8/856/4159503 by gest on 15 M arch 2020 damaged” or have a “serious psychiatric disorder” may cause more harm than good if they become overly invested in their diagnoses and expect disability as inevitable. Educating individuals about the expected course of recovery and providing specifics about their injury severity and the expected duration for their symptoms is essential in aiding in their recuperation, both physically and psychologically.