Background: Emotional abuse is associated with an increased risk for substance use disorders (SUDs) as well as with negative urgency and posttraumatic stress disorder (PTSD) following a subsequent trauma. Both negative urgency and PTSD are key contributors to the relationship between emotional abuse and SUDs when examined separately. A comprehensive model including both factors can inform models of PTSD-SUD comorbidity. Furthermore, the comparison of these mechanistic roles in emotional versus other types of abuse can shed light on the specificity of these effects. Objectives: The present study tested whether negative urgency and PTSD symptom severity serially mediated the relationship between emotional abuse and substance use across two separate samples. Method: Participants were recruited from a detoxification center and completed a battery of surveys examining abuse history, PTSD symptom severity, and impulsivity measures including negative urgency and substance use history during the last 3 months. The samples consisted of predominantly (59% and 62%) males with an average age of 35 (age range: 18-65). The majority of participants (90% and 93%) were Caucasian. Results: Study 1 (N = 368) and Study 2 (N = 274) both found that negative urgency and PTSD symptom severity serially mediated the relationship between emotional abuse and substance use. When comparing indirect effects, both contributed equally. Conclusion: These findings suggest that negative urgency and PTSD symptom severity together account more for the link between emotional abuse and SUDs than either alone and argue for the inclusion of negative urgency in models of PTSD-SUD comorbidity.
Keywords: PTSD; Substance use; detoxification; emotional abuse; negative urgency.