Posttraumatic Stress Disorder, Hostile Cognitions, and Aggression in Iraq/Afghanistan Era Veterans

Objective: Most veterans with posttraumatic stress disorder (PTSD) are not violent, yet research has demonstrated that there is a substantial minority who are at increased risk. This study tested hypotheses regarding hyperarousal symptoms and hostile cognitions (i.e., "hostility") as potential mechanisms of the association between PTSD and physical aggression in a longitudinal sample of Iraq/Afghanistan era veterans. Method: The sample included U.S. veterans between the ages of 18 and 70 who served in the military after September 11, 2001. At baseline, 301 veterans were evaluated for PTSD and completed self-report measures of hostility. At six-month follow-up 275 veterans and their family members or friends reported on the veterans' physical aggression over the preceding interval. Regression models were used to evaluate relationships among PTSD status, hyperarousal cluster symptoms, and hostility at baseline, and physical aggression at six months. Bootstrapping was used to test for the mediation of baseline PTSD and six-month aggression by hostility. Results: PTSD significantly predicted physical aggression over six months, but hyperarousal cluster symptoms did not account for unique variance among the three clusters in the longitudinal model. Hostility partially mediated the association of PTSD at baseline and physical aggression at six months. Conclusions: Hostility may be a mechanism of the association of PTSD and physical aggression in veterans, suggesting the potential utility of targeting hostile cognitions in therapy for anger and aggression in veterans with PTSD.