Objective:Traumatic brain injury (TBI) is increasingly recognized as a risk factor for deleterious mental health and functional outcomes. The purpose of this study was to examine the strength and specificity of the association between deployment-acquired TBI and subsequent posttraumatic stress and related disorders among U.S. Army personnel.Method:A prospective, longitudinal survey of soldiers in three Brigade Combat Teams was conducted 1?2 months prior to an average 10-month deployment to Afghanistan (T0), upon redeployment to the United States (T1), approximately 3 months later (T2), and approximately 9 months later (T3). Outcomes of interest were 30-day prevalence postdeployment of posttraumatic stress disorder (PTSD), major depressive episode, generalized anxiety disorder, and suicidality, as well as presence and severity of postdeployment PTSD symptoms.Results:Complete information was available for 4,645 soldiers. Approximately one in five soldiers reported exposure to mild (18.0%) or more-than-mild (1.2%) TBI(s) during the index deployment. Even after adjusting for other risk factors (e.g., predeployment mental health status, severity of deployment stress, prior TBI history), deployment-acquired TBI was associated with elevated adjusted odds of PTSD and generalized anxiety disorder at T2 and T3 and of major depressive episode at T2. Suicidality risk at T2 appeared similarly elevated, but this association did not reach statistical significance.Conclusions:The findings highlight the importance of surveillance efforts to identify soldiers who have sustained TBIs and are therefore at risk for an array of postdeployment adverse mental health outcomes, including but not limited to PTSD. The mechanism(s) accounting for these associations need to be elucidated to inform development of effective preventive and early intervention programs.; Objective:Traumatic brain injury (TBI) is increasingly recognized as a risk factor for deleterious mental health and functional outcomes. The purpose of this study was to examine the strength and specificity of the association between deployment-acquired TBI and subsequent posttraumatic stress and related disorders among U.S. Army personnel.Method:A prospective, longitudinal survey of soldiers in three Brigade Combat Teams was conducted 1?2 months prior to an average 10-month deployment to Afghanistan (T0), upon redeployment to the United States (T1), approximately 3 months later (T2), and approximately 9 months later (T3). Outcomes of interest were 30-day prevalence postdeployment of posttraumatic stress disorder (PTSD), major depressive episode, generalized anxiety disorder, and suicidality, as well as presence and severity of postdeployment PTSD symptoms.Results:Complete information was available for 4,645 soldiers. Approximately one in five soldiers reported exposure to mild (18.0%) or more-than-mild (1.2%) TBI(s) during the index deployment. Even after adjusting for other risk factors (e.g., predeployment mental health status, severity of deployment stress, prior TBI history), deployment-acquired TBI was associated with elevated adjusted odds of PTSD and generalized anxiety disorder at T2 and T3 and of major depressive episode at T2. Suicidality risk at T2 appeared similarly elevated, but this association did not reach statistical significance.Conclusions:The findings highlight the importance of surveillance efforts to identify soldiers who have sustained TBIs and are therefore at risk for an array of postdeployment adverse mental health outcomes, including but not limited to PTSD. The mechanism(s) accounting for these associations need to be elucidated to inform development of effective preventive and early intervention programs.