Indirect effects of 12-session seeking safety on substance use outcomes: Overall and attendance class-specific effects

Objectives This study examined in- and post-treatment mediation effects of a 12-session dose of Seeking Safety (SS) - an integrative cognitive behavioral treatment for comorbid PTSD and SUDs - on alcohol and cocaine outcomes in comparison to Women's Health Education (WHE) in a seven-site randomized controlled effectiveness trial. Methods Women (n = 353) enrolled in outpatient substance abuse treatment, who had experienced multiple traumas in childhood and/or adulthood and who had comorbid PTSD, were randomly assigned to receive SS or WHE delivered in open enrollment groups for 12 sessions in 6 weeks (unlike the full 25-topic SS protocol). Data were analyzed under two forms of longitudinal mediation analysis, each accounting for changes over time in group membership and group context, respectively. Results Women in SS, compared to WHE, showed significantly steeper decreases in PTSD frequency and severity, which in turn, showed significant impact in reducing both cocaine and alcohol use. This pattern was strongest for those who completed most of the treatment sessions, which was the majority of patients in the trial; these patterns only emerged during the in-treatment phase. Conclusions Use of an integrated approach to PTSD/SUD such as SS can be helpful to more rapidly reduce PTSD, which consequently reduce SUD symptoms, particularly for those who attend most of the available treatment sessions. Scientific Significance This is one of the first studies to illustrate such effects in treating comorbid PTSD and SUD in the context of a highly impaired population delivered by community-based providers.