Differential relationships of PTSD and childhood trauma with the course of substance use disorders

A large body of research documents the link between Posttraumatic Stress Disorder (PTSD) and the course of Substance Use Disorders (SUD). Similar relationships have been reported between Childhood Trauma (CT) and the course of illness in patients with SUD even in the absence of PTSD, but few studies have examined differential effects of PTSD and CT (independent of PTSD) in this population. We used the International Diagnostic Checklist (IDCL) and the Posttraumatic Diagnostic Scale (PDS) to diagnose PTSD in a sample of patients with SUD (N = 459). The Childhood Trauma Questionnaire (CTQ) and the European Addiction Severity Index (EuropASI) were administered to assess childhood trauma and addiction related problems including comorbid psychopathological symptoms. The sample was divided into three groups: patients with experiences of CT and PTSD (CT-PTSD), experiences of CT without PTSD (CT-only), and neither experiences of CT nor PTSD (No trauma) to examine their differential associations with the course and severity of SUD. Patients of both the CT-PTSD (n = 95) and the CT-only group (n = 134) reported significantly higher levels of anxiety and depression as well as more suicidal thoughts and suicide attempts during their lifetime than the No trauma group (n = 209). Regarding most variables a graded association became apparent, with the highest level of symptoms in the CT-PTSD group, an intermediate level in the CT-only group and the lowest level in the No trauma group. The CT-PTSD group also differed in almost all substance use variables significantly from the No trauma group, including a younger age at first use of alcohol and cannabis, more cannabis use in the last month, and more lifetime drug overdoses. Our results confirm the relationships of both CT and PTSD with psychiatric symptoms in patients with SUD. Thus, it seems important to include both domains into the routine assessment of SUD patients. Specific treatments for comorbid PTSD but also for other consequences of childhood trauma should be integrated into SUD treatment programs.