A longitudinal investigation of the association between rumination, hostility, and PTSD symptoms among trauma-exposed individuals.

<bold>Background: </bold>Rumination, defined as perseverative thinking regarding the causes and consequences of psychological symptoms, is a risk and maintaining factor for PTSD. Existing work has largely focused on the extent to which rumination functions as a coping strategy used to avoid traumatic memories and associated emotions. However, rumination may also maintain negative thinking patterns, such as hostility, which has been positively associated with both rumination and PTSD symptoms. The current study therefore investigated the extent to which hostility was a significant mediator of the prospective association between rumination and PTSD symptoms.<bold>Methods: </bold>The sample consisted of 119 trauma-exposed individuals (48.7% female), who completed self-report questionnaires at three time points during a clinical trial.<bold>Results: </bold>When controlling for treatment condition and baseline depressive disorder diagnosis, hostility temporally mediated the effects of rumination on PTSD symptoms. Specificity analyses provided further support for the direction and specific variables examined in this model, such that rumination was positively and uniquely associated with later hostility.<bold>Limitations: </bold>Our findings are limited by the use of a sample in which only 30% of participants met diagnostic criteria for a trauma-related disorder, as well as the administration of the rumination measure at only one time point.<bold>Conclusions: </bold>Results suggest that rumination and hostility may be promising treatment and prevention targets for PTSD symptoms. [ABSTRACT FROM AUTHOR]