Many women with substance use disorders (SUD) have experienced complex psychological trauma including childhood interpersonal victimization. Research confirms that many adults seeking treatment for SUD exhibit co-occuring symptoms of PTSD leading to the implementation of trauma-informed treatment in behavioral health and substance abuse treatment settings. This study examined whether women in trauma-informed treatment for SUD exhibited distinct symptom profiles of simple and complex traumatic stress, and how symptomatology related to women's cumulative trauma history and trauma-informed SUD treatment completion. Traumatic stress symptomatology was examined in two ways: (a) symptom profiles based on intake T-scores on simple and complex posttraumatic stress symptom domains of the Trauma Symptom Inventory (TSI; Briere, 1995), and (b) cumulative traumatic stress symptom complexity (e.g., Briere et al., 2008; Cloitre et al., 2009).

A Ward's method hierarchical cluster analysis with k-means procedure created a typology of traumatic stress symptomatology based upon intake T-scores on seven TSI subscales for 360 women enrolled in trauma-informed SUD treatment programs. As predicted, the clusters varied in the types, severity, and clinical complexity of traumatic stress symptoms reported. Examination of cluster centroids and descriptive data suggested evidence for all three traumatic stress symptom profiles hypothesized: (a) No Traumatic Stress, (b) Simple Posttraumatic Stress, and (c) Complex/Cumulative Traumatic Stress. In addition, the final four-cluster solution revealed a Defensive Avoidant subgroup of substance abusing women characterized by elevated centroid scores on the Defensive Avoidance clinical subscale of the TSI without concurrent elevation of other symptoms of simple or complex traumatic stress.

Women in all clusters reported histories of cumulative, interpersonal trauma, but the prevalence was greatest among women exhibiting complex/cumulative traumatic stress symptomatology. Program completion was similar across traumatic stress symptom clusters in both models of trauma-informed treatment. Implications for research, diagnosis, and intervention are discussed. This study calls for complex-trauma-informed assessment and treatment of co-occurring psychological trauma, traumatic stress, and SUD.