Low neuroticism as an indicator of resilience: a longitudinal study of Danish soldiers before, during and after deployment

<b>Background</b>: Posttraumatic stress disorder (PTSD) is a serious and debilitating condition among military veterans. Exposure to potentially traumatic events (PTEs) may lead to PTSD and PTE sensitivity may be influenced by the personality trait neuroticism.<b>Objective</b>: The current investigation aims to test whether exposure to PTEs during deployment is associated with changes in PTSD symptoms, and whether individual levels of neuroticism are related to resilience or sensitivity to such exposures.<b>Methods</b>: The study sample included 701 Danish soldiers deployed to Afghanistan in 2009. PTSD symptoms were measured pre-, peri- and post-deployment (T1-T3) with the PTSD Checklist-Civilian Version. PTSD symptom load was modelled in a mixed linear model along with an extensive list of covariates. Interactions between time, exposure, and neuroticism were tested in order to assess whether neuroticism moderated the effect of PTEs upon PTSD symptoms.<b>Results</b>: On average, PTSD symptoms decreased from T1 through T3. Factors associated with higher PTSD symptom levels included number of past trauma, neuroticism, and low age at deployment. Interaction analyses showed that individuals with low and medium neuroticism levels displayed no significant change in PTSD symptoms, and individuals with high neuroticism displayed a significant decrease in PTSD symptoms. These changes were consistent across levels of perceived exposure to danger and combat and witnessing the consequences of war.<b>Conclusions</b>: Results indicate that low levels of neuroticism appear to be related to resilience. Individuals with high levels of neuroticism displayed elevated PTSD symptoms across all time points, but contrary to expectations, they reported a significant decrease in PTSD symptoms from pre- to post-deployment.