This survey study (n=121) explored the co-occurrence of PTSD in patients with a substance use disorder (SUD). It was found that SUD patients with PTSD were more likely to use MDMA than those without PTSD and MDMA use was associated with avoidance symptoms. The authors conclude that MDMA use might reflect an attempt to self-medicate to deal with avoidance symptoms however, it may also be the case that MDMA use led to more severe avoidance symptoms.

Abstract

“Background: Adolescent patients with a substance use disorder (SUD) often fulfil the criteria for a co-occurring post-traumatic stress disorder (PTSD). However, it is not clear if these dual-diagnosed adolescents present with unique levels of substance use and how their substance use relates to PTSD symptom clusters.

Objective: To investigate substance use in adolescents with co-occurring PTSD and SUD. Additionally, we explored how the use of specific substances is related to specific PTSD symptom clusters. Method: We recruited n = 121 German adolescent SUD patients, in three groups: no history of traumatic events (TEs) (n = 35), TEs but not PTSD (n = 48), probable PTSD (n = 38). All groups were administered a trauma questionnaire and were asked to report their past-month substance use.

Results: Adolescents with probable PTSD and SUD report a higher frequency of MDMA use than adolescents with no PTSD and no TE (PTSD vs. no TE: U = 510.5, p = .016; PTSD vs. TE: U = 710.0, p = .010). The use of MDMA was more frequent in adolescents with avoidance symptoms (X2 (1) = 6.0, p = .014). Participants report using substances at a younger age (PTSD vs. no TE: U = 372.0, p = .001; PTSD vs. TE: U = 653.5, p = .022) and PTSD symptom onset was on average 2.2 years earlier than first MDMA use (t (26) = −2.89, p = .008).

Conclusions: Adolescent SUD patients with probable PTSD are more likely to use MDMA than SUD patients without PTSD. The use of MDMA was associated with reported avoidance symptoms. The first age of MDMA use is initiated after PTSD onset. It is unclear whether the association of MDMA use with avoidance symptoms is due to efforts to reduce these symptoms or a result of regular MDMA use.”

Authors: Lukas A. Basedow, Sören Kuitunen-Paul, Melina F. Wiedmann, Veit Roessner & Yulia Golub

Summary

Adolescents with a substance use disorder and PTSD often present with unique levels of substance use.

Introduction

Approximately one-third of adults with a psychiatric disorder also have at least one co-occurring psychiatric disorder. These patients present a challenge for mental health professionals in inpatient settings.

Adolescents with post-traumatic stress disorder (PTSD) and substance use disorders (SUDs) often co-occur, and this co-occurrence is associated with increased SUD severity and a situation that makes therapeutic care more challenging.

Three hypotheses have emerged to explain the pattern of co-occurrence of substance use disorder and PTSD in adolescents.

People who engage in high-risk behaviours are more likely to experience traumatic events such as first-hand violence, and subsequently develop PTSD. This self-medication hypothesis has gained much empirical support, and is based on the assumption that SUD symptoms should develop following PTSD symptoms.

The severity of adolescent SUD has been associated with a co-occurring PTSD, but little is known with regard to the use of specific substances and PTSD symptomatology in adolescents.

Previous studies investigating the use of psychoactive substances in adults with PTSD reported conflicting results, with avoidance symptoms being associated with alcohol, benzodiazepine, cocaine, and cannabis use. No research so far could clarify the connection between specific substance use and distinct PTSD symptoms. Additionally, it is unclear if TEs alone might already predispose adolescents to increased substance use and SUD severity.

We conducted this study to explore the relationships between substance use frequency and the three PTSD SCs in adolescent patients with a history of trauma exposure, trauma exposure but without PTSD, and no trauma exposure.

2.1. Participants

Between November 2017 and November 2020, 121 treatment-seeking adolescents were recruited from a German outpatient clinic for adolescent substance abuse. They were divided into three groups based on whether they fulfilled PTSD criteria according to self-report.

A self-report questionnaire was used to screen for traumatic events (TEs) and post-traumatic stress disorder (PTSD) symptoms in adolescents. The UCLA RI-IV is a self-report questionnaire that maps directly onto the DSM-IV intrusion, avoidance, and hyperarousal SCs.

2.2.2. Substance use

Clinical psychologists assessed the extent of substance use by asking about the number of days of past-month tobacco, alcohol, cannabis, MDMA, and amphetamine use, and the age of first use.

2.2.3. SUD diagnosis

The MINI-KID is a diagnostic interview used to evaluate the presence of psychiatric disorders in children and adolescents.

2.2.4. Sociodemographic information

The caregivers of our participants answered 36 questions about their socio-demographic data, including age, gender, education level, and yearly household income.

2.2.5. Procedure

Data collection was embedded into the standard diagnostic procedures at our outpatient clinic. Participants gave written informed consent to the study, which was approved by the Institutional Review Board.

2.2.6. Statistical analysis

All analyses were conducted with IBM SPSS Statistics for Windows, version 27.0 (IBM, Corp, 2020). Chi-square tests were used to assess differences in socio-demographic characteristics between the three groups.

We used chi-square and Kruskal-Wallis tests to compare the prevalence of substances across three groups and performed Mann- Whitney U follow-up tests if any of the omnibus comparisons were significant.

For the analyses, we conducted a Kruskal-Wallis omnibus test, Mann-Whitney U follow-up tests, and six paired sample t-tests to compare age of substance use onset with age of PTSD symptom onset. The level of significance was set to 0.05.

3.1. Sample description

The three groups did not differ in their distribution of SUD diagnoses, level of education, or parental income, or in their past-month tobacco, alcohol, cannabis, MDMA, or amphetamine use. The most common traumas reported were violence and sexual abuse.

3.2. Differences in substance use

We analysed differences in tobacco, alcohol, cannabis, MDMA, amphetamine use frequencies, but did not analyse methamphetamine use frequency.

Participants in the probable PTSD group reported the highest proportion of past-month MDMA users, while participants in the TE group did not differ from the noTE group in days of MDMA use in the last month.

3.3. Relationship between MDMA use and specific PTSD SCs

The past month frequency of MDMA use was higher in participants fulfilling the avoidance criterion compared to those that did not (p = .008).

3.4. Age of onset of PTSD and substance use

Participants in all three groups had a lower age of first substance use than the noTE group and the TE group, with the difference being considered large and moderate, respectively. The age of PTSD onset was significantly lower than the age of first MDMA use.

Discussion

In this study, we found that adolescent SUD patients with probable PTSD use substances at an earlier age, use MDMA more frequently, and start using it after the first occurrence of PTSD symptoms.

The self-medication hypothesis posits that substance use may be a response to co-occurring psychiatric disorders, such as PTSD, and that the substance of choice may have specific PTSD-symptom-relieving effects.

The increased use of MDMA in adolescents with co-occurring PTSD and SUD may be explained by the self-medication hypothesis, since MDMA has been shown to decrease distress induced by the different PTSD SCs. MDMA use is not associated with hyperarousal, but with increased body temperature and increased blood pressure, which might explain why the intrusion SC is not associated with its use.

This study suggests that MDMA use might be associated with avoidance symptoms, and that this association might have clinical implications. However, this study has little bearing on the discussion surrounding MDMA as an adjunct for PTSD therapy.

MDMA use might worsen subclinical PTSD symptoms, because it is associated with increased psychopathology in the Symptom Checklist-90-R, and with psychiatric symptoms such as depression, prodromal psychotic symptoms, or depersonalization. Furthermore, illicit MDMA use may further increase the risk of negative consequences. Adolescent PTSD patients start using MDMA two years after the first onset of symptoms, which is in line with research showing that adolescent mental health symptoms occur later than MDMA use.

We found that adult alcohol use was associated with co-occurring PTSD and SUD, but this association was compared to the level of symptoms between people who drink alcohol and people who do not.

The results might be in line with previous findings because our sample consisted of adolescents drinking alcohol at elevated levels already. Furthermore, since MDMA emerged as a factor nonetheless, the MDMA use might be more relevant for patients with PTSD and SUD than other substances used at the same time.

4.1. Limitations

This study consists of cross-sectional, retrospective data, and is limited to adolescent, treatment-seeking SUD patients. It cannot determine the role MDMA use might play in adolescents with only a PTSD diagnosis, and its results have a low power to detect potential effects.

Testing for socio-demographic confounders was not possible, and a large number of tests were conducted increasing the likelihood of reporting false-positive results.

4.2. Conclusion

Adolescents with co-occurring probable PTSD were more likely to have used MDMA in the past month and use it in higher frequency than adolescents with only a SUD, regardless of additional TE.