PTSD Symptom Clusters and Suicide Attempts among High-Risk Military Service Members: A Three-Month Prospective Investigation

Objective: Suicide rates within the U.S. military are elevated, and the assessment and treatment of posttraumatic stress disorder (PTSD) has been identified as one potential conduit for suicide risk reduction. Despite increased interest in examining whether PTSD symptom clusters differentially predict suicide-related outcomes, to our knowledge no study has examined this question utilizing a prospective design for which suicide attempts is the outcome. Thus, the present study assessed whether PTSD symptom clusters differentially predict suicide attempts at 3-month follow-up and examined the moderating role of combat exposure. Method: Participants were 758 military service members referred for psychiatric evaluation for suicide-related concerns and who provided both baseline and follow-up data (76.8% male, Mage 25.20 y [SDage 6.22 y], 61.6% White/Caucasian, 28.2% combat-exposed). Baseline PTSD symptom clusters scores were derived from an abbreviated version of the PTSD Checklist'Military Version (PCL-M). Suicide attempts occurring from baseline to follow-up were assessed with the Suicide Attempt Self-Injury Interview (SASII). Logistic regression models were utilized, controlling for baseline suicide risk severity (i.e., frequency of suicidal ideation, levels of suicidal intent, past suicide plans and attempts) and sociodemographic characteristics. Results: The hyperarousal symptom cluster was the only significant predictor of subsequent suicide attempts and, moreover, this association was significant for combat-exposed service members but not for non-combatexposed service members. Conclusions: PTSD hyperarousal symptoms, characterized in part by overarousal (e.g., agitation), should be considered in military suicide risk assessment and prevention efforts, particularly for combat-exposed service members.