Pre-deployment aggressiveness, combat exposure and moral injury as contributors to posttraumatic stress symptoms among combatants: A two-year prospective study.

Combatants who are exposed to events which transgress deeply held moral beliefs might face lasting psychopathological outcomes such as Moral Injury (MI) and posttraumatic stress symptoms (PTSS). However, insight about pre-deployment personality factors which might facilitate the MI process and its negative consequences is sparse. In this prospective study, we examined pre-deployment aggressiveness as a possible predictor of exposure to combat and potentially morally injurious events (PMIEs), trauma-related guilt and shame and PTSS among Israeli active-duty combatants. A sample of 335 active-duty Israeli combatants participated in a 2.5-year prospective study with three waves of measurements (T1: 12 months before enlistment, T2: 6 months following enlistment-pre deployment, and T3: 18 months following enlistment-post deployment). Participants' characteristics were assessed via semi-structured interviews (T1) and validated self-report measures of aggressiveness (T2), combat exposure, PMIEs and PTSS (T3) between 2019 and 2021. Results show that higher levels of pre-deployment aggressiveness predicted both combat exposure and PMIEs-'betrayal'. Combat exposure mediated the association between aggressiveness and PTSS post deployment. Importantly, pre-deployment aggressiveness was significantly associated with the PMIEs-'betrayal' that are associated with trauma-related guilt and shame, which in turn were associated with high levels of PTSS post deployment. Our results highlight the implications of pre-deployment aggressiveness for different forms of exposure to potentially traumatic events during military service. Identification of at-risk combatants for PTSS following exposure to PMIEs of betrayal might provide these combatants with a tailor-made type of preparation regarding moral and ethical situations, which should be investigated in future studies.