Background: Post-traumatic stress disorder (PTSD) and substance use disorders (SUDs) often co-occur in adolescent patients. Previous research has shown that these patients difer from SUD patients without PTSD in terms of their sub‑ stance use patterns. In this study, we aimed to test whether substance use in this population is related to an attempt to self-medicate PTSD-related symptoms.
Methods: German adolescent patients (aged 13–18 years) at an outpatient clinic for SUD treatment, n=111 (43% female), completed a self-designed questionnaire on use motives, a measure of PTSD-related experiences, and under‑ went a standardized psychiatric interview including structured substance use questions. Participants were subse‑ quently classifed as ‘no traumatic experiences (‘noTEs’ but SUD), ‘traumatic experiences but no current PTSD diagnosis’ (‘TEs’ with SUD), and ‘PTSD’ with SUD. After establishing a self-designed motive measurement through exploratory and confrmatory factor analyses, we calculated non-parametric group diferences and a mediation analysis in a linear regression framework.
Results: The past-year frequency of MDMA use was highest in the PTSD group and lowest in the noTE group (H (2)=7.2, p=.027, η2=.058), but no diferences were found for frequencies of tobacco, alcohol, cannabis, or stimulant use (all H≤4.9, p≥.085, η2≤.033). While controlling for sex, the three groups showed a similar pattern (highest in the PTSD group and lowest in the noTE group) for coping scores (F (103)=5.77, p=.004, η2=.101). Finally, mediation analyses revealed an indirect efect of coping score (b=0.61, 95% CI [0.29, 1.58], p=.145) on the association between group membership and MDMA use frequency.
Conclusions: In adolescent SUD patients, we found an association of current PTSD and lifetime traumatic experi‑ ences with higher MDMA use that could be partially explained by substance use being motivated by an attempt to cope with mental health symptoms. This indicates a coping process involved specifcally in MDMA use compared to the use of other psychoactive substances, possibly due to unique psychoactive efects of MDMA.