Trauma and ICD-11 PTSD in substance use disorder treatment: a Danish multi-site study

Previous research has indicated high levels of PTSD among people with substance use disorder (SUD). This study expands that work to a Danish SUD population, assessing the prevalence of ICD-11 PTSD diagnoses, sociodemographics, and trauma- and substance-related factors. We also compare differences between individuals in treatment for alcohol use disorder (AUD) and drug use disorder (DUD). The study used a multi-site approach, with data from five Danish SUD treatment settings. A total of 1347 adults were interviewed as part of an initial structured screening for SUD treatment. Participants were assessed using ICD-11 PTSD criteria. Approximately 25% of individuals in treatment met criteria for probable PTSD, with an additional 15% evidencing subclinical PTSD. PTSD prevalence was higher in DUD treatment than AUD treatment. The study also highlights significant differences in social functioning and clinical profiles between the two groups. The high prevalence of PTSD symptoms among individuals in SUD treatment indicates a need for targeted interventions. PTSD should be a particular focus in DUD treatment due to the high vulnerability and prevalence of trauma-related symptoms in this subgroup.