Eye Movement Desensitization and Reprocessing as a Treatment for Substance Use Disorders

Study Overview
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Brief Summary
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Substance Use Disorders (SUD) are often comorbid with psychological trauma, however, the complex interaction between the two is not yet fully understood. Most addiction-specialized professionals do not engage in exploring past traumatic experiences of the patients due to personal, professional, and educational barriers. Therefore, psychological trauma remains highly undetected and its contribution to the development and maintenance of SUD is neglected. This compromises the therapeutic results of most interventions, with relapse rates in SUD still remaining impressively high. EMDR is one of the most effective interventions for Post-Traumatic Stress Disorder (PTSD), and has been applied to other disorders that are often comorbid with trauma, such as psychosis and depression, with promising results. Nevertheless, its application in SUD is still limited. Taken altogether, there is a need to clarify the efficacy of Eye Movement Desensitization and Reprocessing (EMDR) therapy in SUD, as well as the mechanisms of action that mediate its potential therapeutic effects. The aim of this study is to 1) determine the efficacy of EMDR therapy in patients with SUD comorbid with psychological trauma, as well as whether changes in these clinical variables correspond to changes in salivary cortisol levels- a robust marker of the Hypothalamic-Pituitary-Adrenal (HPA) axis; 2) investigate the mechanisms of action of EMDR therapy, paying special attention to the key role that the cerebellum might play in mediating its therapeutic effects.

Official Title
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What Works and Why? Eye Movement Desensitization and Reprocessing as a Potential Treatment for Substance Use Disorders

Conditions
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Substance Use Disorders

Intervention / Treatment
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* Behavioral: EMDR
* Behavioral: TAU


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: A primary DSM-5 diagnosis of moderate to severe SUD, assessed by a clinical interview. No active drug consumption. Having experienced one or more traumatic events, assessed by the Life Event Checklist DSM-5 (LEC-5) and the Childhood Trauma Questionnaire (CTQ). Current posttraumatic symptoms, evaluated with the Impact Event Scale-Revised (IES-R). Aged from 18 to 65 years old. Sign an informed consent to participate in the study. Capable of speaking and comprehending Catalan or Spanish. Exclusion Criteria: Having received a trauma-focused therapy within the last 5 years. Severe dissociative symptoms according to the Dissociative Experience Scale (DES). Presence of acute suicidal ideation. Acute episode of a comorbid psychiatric disorder. Severe cognitive impairments. Medical illness that compromises the HPA-axis. Long-term exposure to corticoids. Claustrophobia. Subjects with pacemakers. Presence of metallic objects within the body. Pregnancy

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 65 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Eye Movement Desensitization and Reprocessing therapy<br>8 to 10 individual 60-minutes sessions over 2 months. | Behavioral: EMDR<br>* The first session consists of recording the patient's history. In the second session the therapist evaluates the presence of coping mechanisms of the patient and, if necessary, suggests extra coping techniques. The following sessions are devoted to the reprocessing process. During these sessions, a target memory is identified and processed using EMDR. After a total of 8-10 sessions, it is expected that the patient will have achieved physiological reconciliation, relieved distress, and the ability to reformulate negative beliefs.<br>Behavioral: TAU<br>* treatment as usual for substance use disorders<br>|
| Active Comparator: Treatment as usual<br>Same periodicity as the experimental group and at the same time range. | Behavioral: TAU<br>* treatment as usual for substance use disorders<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| time to relapse | Relapse is defined as a return to the addictive behavior, different from a punctual consumption, which is considered as a lapse. This will bee measured by the Time Line Follow Back self-report (TLFB) | 2 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| changes in functional connectivity | measured by resting-state fMRI | 2 months | 
| percentage of conditioned eyeblink responses (CR) | measured by the Eyeblink Conditioning System | 2 months | 
| CR latency, CR onset, and CR amplitude. | measured by the Eyeblink Conditioning System | 2 months | 
| Hair and salivary cortisol levels | Comparison of the Area Under the Curve pre and post treatment | 2 months | 
| Craving | Self-report measurement | 2 months 3 months and 5 months | 
| Total amount of substance consumed during the previous month | measured by the TLFB | 2 months, 3 months and 5 months | 
| Changes in depressive symptomatology | measured by Beck's Depression Inventory (BDI) | 2 months, 3 months and 5 months | 
| Changes in anxious symptomatology | measured by The State-Trait Anxiety Inventory (STAI) | 2 months, 3 months and 5 months | 
| Changes in posttraumatic symptomatology | measured by Clinician-Administered PTSD Scale (CAPS) | 2 months, 3 months and 5 months | 
| Changes in global functioning | measured by Functioning Assessment Short Test (FAST) | 2 months, 3 months and 5 months |