Bidirectional relationships between trauma exposure and posttraumatic stress: a longitudinal study of Detroit residents.

Previous research has documented bidirectional relationships between trauma exposure and posttraumatic stress (PTS), such that individuals who are exposed to more traumatic events are at increased risk of developing PTS, and more severe PTS is associated with more subsequent trauma exposure. However, the empirical literature is limited by a lack of longitudinal studies that include continuous measures of PTS, differentiate between assaultive (e.g., sexual assault, being held up or mugged) and nonassaultive (e.g., serious illness, natural disaster) trauma, and focus on urban contexts. The purpose of this study was to fill these gaps through testing 3-wave cross-lagged panel models of exposure to assaultive and nonassaultive traumatic events and PTS among a large sample of urban-dwelling adults (N = 1,360; 84.4% non-Hispanic Black). In the model including assaultive trauma, more Wave 2 assaultive events were associated with significantly higher Wave 3 PTS. In contrast, in the model including nonassaultive trauma, higher Wave 1 and Wave 2 PTS were associated with more nonassaultive events at Waves 2 and 3, respectively. Taken together, the findings suggest a cycle of adversity wherein urban residents who have experienced assaultive trauma are at risk of more severe PTS, which in turn increases risk for exposure to nonassaultive trauma. This cycle could be tested directly in future studies through models including both types of events. Additional research on the mechanisms that underlie the pathways between PTS and traumatic events could also have implications for policy and practice.