PT-STRESS Study: Predicting Treatment Success and Dealing With Non-response in the Treatment of PTSD

Stress Disorders, Post-Traumatic Clinical Trial

— PT-STRESS  

Official title:

PT-STRESS Study: A Two-phase RCT Aimed at Predicting Treatment Success and Dealing With Non-response in the Treatment of PTSD; by Alternating Between Two Trauma-focused Treatments (EMDR/PE) or by Switching to Interpersonal Therapy (IPT)

Clinical Trial Details — Status: Recruiting

Administrative data

• NCT number: NCT06279598
• Other study ID #: UniversityGroningen
• Status: Recruiting
• Phase: N/A
• Start date: January 1, 2024
• Est. completion date: August 31, 2032

Study information

• Verified date: February 2024
• Source: University of Groningen
• Contact: Maarten K van Dijk, PhD
• Phone: +31 0570-604000
• Email: m.vandijk[@]dimence.nl
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial Summary

The aim of this study is to increase understanding of the effectiveness and efficiency of psychological treatment for adult patients with posttraumatic stress disorder -PTSD- and to make it more personalized.

Key questions:

1. Which predictors of treatment success influence treatment outcome of patients with PTSD who receive the three psychotherapeutic treatments investigated in this study?

2. Which specific moderators can be identified with regard to the different psychotherapies (Eye Movement Desensitization and Reprocessing -EMDR-; Prolonged Exposure -PE-; and Interpersonal Psychotherapy -IPT- in the second phase)?

3. In patients with PTSD, does offering another proven effective form of trauma-focused psychotherapy (PE after EMDR, or EMDR after PE) improve symptoms following insufficient response to a first trauma-focused treatment?

4. Is switching from a trauma-focused therapy to a non-trauma-focused treatment (IPT) a more effective strategy for dealing with non-response to a first proven effective psychotherapeutic treatment compared to switching to another trauma-focused therapy?

5. Are there differences in treatment tolerance and differences in dropout rates between PE, EMDR and IPT?

Secondary goals:

• Investigating the extent to which therapist allegiance to a specific therapy method affects outcomes;

• Investigating whether the quality of therapy implementation or the treatment integrity ('adherence/ competence') affects treatment outcomes;

• Investigating how much the quality of the therapeutic alliance influences outcomes.

Participants receive treatment and will complete questionnaires. The study is conducted in two phases. Its aim is to compare two different trauma-focused treatments (EMDR and PE) for patients with PTSD to one another and with a nontrauma-focused psychotherapy (IPT) and to investigate possible predictors and moderators for treatment success. Patients will first be randomized to PE or EMDR in the first treatment phase. After this first phase, non-responders are re-randomized for a second phase of treatment. They receive either the alternative phase 1 trauma-focused psychotherapy or IPT as non-trauma-focused therapy. In phase 1 researchers will compare the PE and EMDR group to see which treatment is most effective for whom. In phase 2 researchers will compare the trauma-focused treatments (PE and EMDR group) with the nontrauma-focused treatment (IPT group) to see which treatment is most effective for whom.

Description:

Background of the study:

The symptoms of posttraumatic stress disorder (PTSD) follow exposure to a traumatic event and are accompanied by significant functional limitations. PTSD is very common: a multinational study shows a lifetime prevalence of 3.9%. Effective treatment options exist for people with PTSD, with Eye Movement Desensitization and Reprocessing (EMDR) and Prolonged Exposure (PE; a specific form of trauma-focused Cognitive Behavioral Therapy, T-CBT) both listed as first-choice interventions in the Dutch standard of care for psychotrauma and stressor related disorders. About 40% of patients with PTSD do not benefit sufficiently from either of the aforementioned guideline treatments and about 18% of patients do not complete a trauma-focused treatment (treatment dropout). Knowledge about general predictors of treatment success in psychotherapy is limited, making it currently impossible to predict which patient will or will not benefit from which specific psychotherapeutic treatment (i.e., EMDR vs. PE). Little scientific knowledge exists about optimal follow-up treatment when patients insufficiently benefit from their initial treatment. For patients who drop out (e.g. from inability to tolerate exposure to traumatic memories) or do not benefit from exposure therapies, an alternative is to switch not to another proven effective trauma-focused intervention, but to a non-trauma-focused intervention. A suitable non-traumafocused treatment is Interpersonal Psychotherapy. Previous research suggests that IPT can be an effective first-line treatment option, but the effectiveness of IPT as a second treatment step for people with PTSD who have not responded to a trauma-focused psychotherapy has never been investigated. We hypothesize that IPT will yield greater symptom reduction and less dropout for patients with PTSD who do not respond to a course of trauma-focused psychotherapy compared to switching to another trauma-focused therapy.

Study population:

Subjects are recruited from Dimence, a mental health institution in the Netherlands. Subjects are recruited from patients who register for outpatient treatment within the Dimence division "Specialistic Diagnostics and Treatment" with a primary diagnosis of PTSD. It concerns adults between 18 and 65 years old, both men and women.

Intervention:

Half of initially non-responsive patients will be treated with the non-trauma-focused intervention interpersonal therapy (IPT) in phase 2 of the study. The first and second phases will offer the trauma-focused treatments Prolonged Exposure and EMDR.

• Interpersonal Psychotherapy (IPT) does not target the memories of a traumatic event but the interpersonal consequences of trauma, seeking to improve affective and interpersonal functioning that PTSD symptoms have disrupted. PTSD following a traumatic life event produces social withdrawal and a blunted, inhibited emotional life, disrupting interpersonal functioning. IPT helps benumbed patients recognize and tolerate their feelings so they can use them to handle their social environment, determine who is trustworthy, and mobilize protective social supports. IPT addresses patient emotions and their relationship to interpersonal interactions. As patients recognize their feelings, the therapist helps patients to name, normalize, and use their feelings rather than seeing them as an additional threat.

• In Prolonged Exposure, patients directly confront traumatic memories and cues and learn to expose themselves to terrifying but not dangerous stimuli to achieve habituation or extinction. The current study will use a protocol-based treatment of Cognitive Behavioral Therapy for PTSD that includes imaginal and in vivo exposure.

• In EMDR, patients are distracted from the traumatic memories by a dual attention task, usually using eye movements. This study will use a protocolled EMDR treatment for PTSD.

Nature and extent of the burden and risks associated with participation, benefit and group relatedness (if applicable):

Major adverse events are not expected as these have not been documented in previous studies. The greatest burden on subjects is completing the questionnaires necessary to answer the primary research questions. In phase 1, this totals approximately 10.5 hours (with baseline measurement the most extensive and subsequent weekly measurements); for patients treated for an additional 8 weeks in phase 2, completing the questionnaires takes approximately another 6 hours. A patient participating in both treatment phases therefore spends a total of approximately 16.5 hours completing assessments. The prescription of patients taking medication must be stable prior to the study, and then not changed during the study, unless necessary due to a crisis or serious side effects. Patients receive treatment sessions twice a week, which is relatively frequent compared to usual treatment, but research shows that dropout is lower with two weekly sessions. Study participation further assures patients that the treatments they receive are performed as intended by the therapy-developer because therapists receive supervision and checks are made to ensure treatment integrity.

Recruitment information / eligibility

• Status: Recruiting
• Enrollment: 442
• Est. completion date: August 31, 2032
• Est. primary completion date: May 20, 2031
• Accepts healthy volunteers: No
• Gender: All
• Age group: 18 Years to 65 Years

Eligibility

Inclusion Criteria:

• Adults between the ages of 18 and 65 who were classified with a primary diagnosis of PTSD (based on the DSM-5 criteria).

• Adults who are willing to participate in the study (informed consent)

Exclusion Criteria:

• Insufficient proficiency in the Dutch language.

• Patients who cannot follow the treatment protocol (for example due to prolonged absence) are excluded from the study.

• Patients who use medication that is not stable. If properly set to the last prescribed medication by the doctor there will be advised to continue and referably not change the medication and its dose during treatment, unless necessary in connection with side effects, crisis, etc.

• Patients that already received an evidence-based form of trauma-oriented treatment for PTSD in the past year and for sufficient treatment duration, in accordance to the Dutch professional practice guidelines (reference: Akwa GGZ (2020, December 1). GGZ Standaarden. Psychotrauma- en stressorgerelateerde stoornissen. Retrieved September 29, 2022, from https://www.ggzstandaarden.nl/zorgstandaarden/psychotrauma-en-stressorgerelateerde-sto ornissen/introductie).

• Patients with serious suicidality that requires acute intervention and structural addition of additional treatment interventions.

• Patients with an intellectual disability.

• Patients with a serious addiction as a comorbid problem.

• Patients with an acute mania or a psychotic state.

Related Conditions & MeSH terms

• Stress Disorders, Post-Traumatic

Intervention

Behavioral:
• Prolonged Exposure therapy
This concerns a form of psychotherapy for PTSD.
• Eye Movement Desensitization Reprocessing (EMDR)
This concerns a form of psychotherapy for PTSD.
• Interpersonal Psychotherapy (IPT)
This concerns a form of psychotherapy for PTSD.

Locations

Country	Name	City	State
Netherlands	Dimence	Deventer

Sponsors (2)

Lead Sponsor	Collaborator
University of Groningen	Dimence

Country where clinical trial is conducted

Netherlands, 

References & Publications (31)

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* Note: There are 31 references in all — Click here to view all references

Outcome

Type	Measure	Description	Time frame	Safety issue
Other	Age	We are investigating generic predictors of treatment success and specific moderators based on the scientific literature. Further, we have added several instruments to match those that Wibbelink et al. (2021) use in their research in order to be able to collaborate in future data analyses (PAI analysis).; The first demographic variable is age.	Measured at baseline.
Other	Gender	We ask about gender.	Measured at baseline.
Other	Education	We ask about the level of education.	Measured at baseline.
Other	Employment	We ask about employment status.	Measured at baseline.
Other	Marital status	We ask about marital status.	Measured at baseline.
Other	Ethnicity/race	We ask about ethnicity/race.	Measured at baseline.
Other	Medication use	We ask about medication use.	Measured at baseline.
Other	Treatment history	We ask about treatment history.	Measured at baseline.
Other	Mini-Schedules for Clinical Assessment in Neuropsychiatry (mini-SCAN)	The Mini-Schedules for Clinical Assessment in Neuropsychiatry is a shortened version of the SCAN 2.1 developed by the World Health Organization (WHO). The Mini-SCAN is a semi-structured diagnostic interview that determines the most common DSM-5 (formerly DSM-IV Axis I) diagnoses using a diagnostic algorithm. The instrument is administered at baseline in the study to determine comorbidity of other disorders with PTSD, including depression, anxiety, and substance use disorders.	Measured at baseline.
Other	Life Events Checklist for DSM-5 (LEC-5)	The Life Events Checklist for DSM-5 (LEC-5) is often used as a standard lead-in to the CAPS-5 to determine Criterion A validity. The LEC-5 comprises 17 items.	Measured at baseline.
Other	The Childhood Trauma Questionnaire-Short Form (CTQ-SF)	The Childhood Trauma Questionnaire-Short Form (CTQ-SF) will be administered at baseline to assess the severity of five types of child abuse: emotional abuse, physical abuse, sexual abuse, emotional neglect and physical neglect. The CTQ-SF consists of 28 items.	Measured at baseline.
Other	Symptom Checklist-90 (SCL-90), Hostility subscale	The "Hostility" subscale of the Symptom Checklist-90-Revised (SCL-90-R) will be used to measure anger. This subscale of the SCL-90-R consists of 6 items rated on a 5-point Likert scale ranging from 0 ('not at all') to 4 ('extremely') and assesses anger-related thoughts, feelings, and actions.	Measured at baseline and at the end of treatment in phase 1 (= after 8 weeks).
Other	Experiences in Close Relationships-Relationship Structures (ECR-RS)	General attachment style will be measured using the Experiences in Close Relationships-Relationship Structures questionnaire (ECR-RS). The ECR-RS comprises 9 items rated on a 7-point Likert scale ranging from 1 ('completely disagree') to 7 ('completely agree). The ECR-RS measures attachment-related avoidance and attachment-related anxiety.	Measured at baseline and at the end of treatment in phase 1 (= after 8 weeks).
Other	The Brief Experiental Avoidance Questionnaire (BEAQ)	The Brief Experiential Avoidance Questionnaire (BEAQ) will be used to measure experiential avoidance. The BEAQ measures six different domains: behavioral avoidance, fear aversion, suppression, procrastination, repression/denial and distress endurance. The BEAQ comprises 15 items rated on a 6-point Likert scale from 1 ('strongly disagree') to 6 ('totally agree').	Measured at baseline and at the end of treatment in phase 1 (= after 8 weeks).
Other	Improving Access to Psychological Therapies (IAPT)	Social problems (including housing problems, unemployment, social isolation) will be assessed with a list of social problems derived from the Improving Access to Psychological Therapies (IAPT) program.	Measured at baseline and at the end of treatment in phase 1 (= after 8 weeks).
Other	Posttraumatic Cognitions Inventory (PTCI)	The Posttraumatic Cognitions Inventory (PTCI) is a questionnaire consisting of 33 items that assess trauma-related cognitions measured in three domains: negative cognitions about oneself, negative cognitions about the world, and self-blame.	Measured at baseline and at the end of treatment in phase 1 (= after 8 weeks).
Other	Trauma Related Guilt Inventory (TRGI)	The Trauma Related Guilt Inventory (TRGI) will be administered to measure feelings of guilt related to the trauma. The questionnaire consists of 32 items rated on a 5-point Likert scale.	Measured at baseline and at the end of treatment in phase 1 (= after 8 weeks).
Other	Trauma Related Shame Iventory (TRSI)	A Dutch translation of the Trauma Related Shame Inventory (TRSI) will be administered to measure shame. Shame is defined in the TRSI as a negative and painful self-evaluation in the traumatic context and a tendency to withdraw and hide from others. The questionnaire comprises 24 items rated on a 4-point Likert scale from 1 ('not true for me') to 4 ('completely true for me').	Measured at baseline and at the end of treatment in phase 1 (= after 8 weeks).
Other	Working Alliance Questionnaire shortened version (WAV-12)	The therapeutic relationship will be measured with the Working Alliance Questionnaire - shortened version (WAV-12). The WAV-12 is derived from the WAV-36, the Dutch translation from the Working Alliance Inventory (WAI). The questionnaire measures the bond between patient and therapist, agreement on the goals of treatment and agreement on the tasks in therapy. The WAV-12 consists of 12 items rated on a 5-point Likert scale from 1 ('rarely or never') to 5 ('always').	Measured every week for 8 weeks in phase 1 and measured every week of 8 weeks in phase 2 of the study.
Other	Expectancy rating (patients and therapists)	An 'expectancy rating' will be used to assess the expectations of patiens and practitioners of the treatment methods offered in the study (Prolonged Exposure, EMDR and IPT).This expectancy rating is administered at baseline and comprises 3 items (one about Prolonged Exposure, one about EMDR and one about IPT) in which patients and practitioners assess the expectation that the therapy will help the patient on scale from 0 ('not at all') to 100 ('maximum').	Measured at baseline.
Primary	PTSD Checklist for DSM-5 (PCL-5)	The primary outcome measure for the effectiveness of the treatment in both phases is symptom reduction (less burden of PTSD symptoms) measured with the PTSD checklist for the DSM-5 (PCL-5). The Dutch version of the PCL-5 will be used, the PCL-5 is administered at baseline and repeated weekly. The PCL-5 is a self-report questionnaire of 20 items about the DSM-5 symptoms of PTSD. This measure will be used to monitor symptom change during and after treatment in both phases of the study.	Measured every week for 8 weeks in phase 1 and measured every week of 8 weeks in phase 2 of the study.
Secondary	Clinician-Administered PTSD Scale for DSM-5 (CAPS-5)	The Dutch version of the CAPS-5 will be used as it is "the gold standard" in PTSD assessment. The CAPS-5 is a 30-item structured clinical interview that we will use, among other things, to determine the current (past month) diagnosis of PTSD and to assess improvement in symptoms since a previous CAPS administration.	Measured at baseline, at the end of treatment in phase 1 (= after 8 weeks) and at the end of the treatment in phase 2 (= after 16 weeks = end of the study).
Secondary	International Trauma Questionnaire (ITQ)	The Dutch version of the ITQ will be used: "Internationale Trauma Vragenlijst" (ITV). The International Trauma Questionnaire (ITQ) is a self-report questionnaire consisting of 18 items that measures complex PTSD (C-PTSD) symptoms according to the diagnostic criteria of the 11th revision of the International Classification of Diseases (ICD-11; World Health Organization).	Measured at baseline, at the end of treatment in phase 1 (= after 8 weeks) and at the end of the treatment in phase 2 (= after 16 weeks = end of the study).
Secondary	Hospital Anxiety and Depression Scale (HADS)	The Dutch version of the HADS will be used. The Hospital Anxiety and Depression Scale is a 14-item self-report questionnaire and can be used to measure levels of anxiety and depression.	Measured every week for 8 weeks in phase 1 and measured every week of 8 weeks in phase 2 of the study.
Secondary	Mental Health Continuum Short Form (MHC-SF)	The Dutch version of the MHC-SF will be used: the Dutch short-form Mental Health Continuum. The MHC-SF comprises 40 items that measure emotional well-being, psychological well-being and social well-being.	Measured at baseline, at the end of treatment in phase 1 (= after 8 weeks) and at the end of the treatment in phase 2 (= after 16 weeks = end of the study).
Secondary	Positive and Negative Experiences of Psychotherapy questionnaire (PNEP)	The Dutch version of the self-report questionnaire Positive and Negative Effects of Psychological Treatment (PNEP) will be used to assess both positive and possibly unfavorable and adverse events in psychological treatments. The Dutch questionnaire consists of 3 questions and 71 items.	Measured at baseline, at the end of treatment in phase 1 (= after 8 weeks) and at the end of the treatment in phase 2 (= after 16 weeks = end of the study).