The effectiveness of Prolonged Exposure (PE) and Eye Movement Desensitization and Reprocessing (EMDR) in treating Posttraumatic Stress Disorder (PTSD) has been well established. Indeed, they are recommended as first line treatments for PTSD in international treatment guidelines.

People who experience psychosis have traditionally been excluded from these trials. This is despite the fact that PTSD is a common comorbidity in psychosis (with 12.4% of people with psychosis also meeting criteria for PTSD) and that the presence of PTSD is associated with worse social and psychiatric outcomes in this group. The biological and psychological sequelae of trauma are also implicated in the genesis and maintenance of psychosis itself.

There has been some preliminary evidence for trauma-focused therapies being safe and effective for people experiencing psychosis. Despite this, the status quo of exclusion of people with psychosis from receiving evidence-based treatments for PTSD symptoms has remained. Van den Berg and colleagues’ RCT is long overdue and is a potential game changer in the landscape of psychological treatments for people experiencing psychosis… I hope.

Methods

The study was a single blind randomised clinical trial with three arms:

1. PE therapy
2. EMDR therapy
3. Wait list

Participants (n=155) were recruited from 13 Dutch outpatient services for people with severe mental health difficulties.

Inclusion criteria were:

• Age 18-65 years
• A lifetime diagnosis of a psychotic disorder or a mood disorder with psychotic features as assessed by the MINI plus
• The presence of PTSD as assessed by the Clinician administered PTSD scale (CAPS), using DSM-IV-TR criteria

Exclusion criteria were:

• An acute suicide risk
• Changes in antipsychotic or antidepressant medication regimen within 2 months before the assessment
• Insufficient competence in the Dutch language
• Severe intellectual impairment, defined as an estimated IQ of 70 or less
• Not being able to travel (or be accompanied) to the outpatient service
• Current involuntary admission in a closed ward
• The presence of current psychotic symptoms was not an exclusion criterion.

The primary outcome measure used was the CAPS, which yielded a PSTD diagnosis and symptom severity score.

Secondary outcome measures were the Posttraumatic Symptom Scale Self-Report, which measures self-reported frequency of PTSD symptoms and the Post-traumatic Cognitions Inventory, which measures trauma-related cognitive distortions. Participants were assessed at baseline, post-treatment and at six-month follow-up.

Data were analysed as intent to treat with linear mixed models and generalized estimating equations.

Interventions

Participants randomised to wait list received standard multi-disciplinary care for psychosis provided by Dutch assertive outreach teams.

Participants randomised to receive either PE or EMDR therapy received eight weekly, 90-minute sessions, within a 10-week timeframe. Both therapies were conducted according to standard protocols (Foa et al. 2007, and Shapiro, 2001). Therapists were 19 clinical psychologists and one psychiatrist. All undertook training in PE and EMDR and provided two supervised treatments as part of their training. Therapists had four hours of group supervision each month, with additional supervision available by phone or email on request.

Results

• Both PE and EMDR were more effective than usual care in reducing PTSD symptoms and achieving loss of PTSD diagnosis
• No differences were found between the two active treatments in head to head comparisons
• The drop out rate was low and comparable to that of other trauma-focused treatment trials
• Change rates in diagnostic status were similar to those found in trauma-focused treatment trials in general samples
• Both treatments were found to be safe and did not result in severe adverse events

Conclusion

The authors concluded:

This study demonstrates that standard PE and EMDR protocols are effective, safe, and feasible in patients with psychosis and comorbid PTSD without using stabilizing psychotherapeutic interventions.

Strengths

• The treatments used standard protocols of PE and EMDR, meaning that there is good potential for implementation in routine clinical practice. There is a common perception that in order to treat PTSD in people experiencing psychosis, clinicians need to have specialist skills in treating both PTSD and Psychosis, often meaning that neither clinicians in psychosis services, nor clinicians in specialist trauma services feel confident to do so. These results would suggest that this is not the case, that clinicians trained in standard PE and EMDR would not need to adapt their treatment protocol to treat PTSD with comorbid psychosis.
• The authors were rigorous regarding incidents of un-blinding. There were 27 incidents of un-blinding and in these instances a different assessor repeated the whole assessment. Being rigorous regarding blinding is of great importance when a primary outcome measure is a clinician rated measure (such as the CAPS).

Weaknesses

• It was not clear from the paper how experienced the treating clinicians were with psychosis and whether they were embedded in the multi-disciplinary treating team; both of which would have implications for translating this protocol to real world practice.
• The level of supervision (from experts in the field) that therapists received during the study was clearly important to ensure fidelity to the protocol, but may limit the results in terms of generalisability to real world practice, where this level of support may not be feasible.
• I was also disappointed that the authors did not report on the effects of PE and EMDR on psychotic symptoms, given the posited link between trauma/PTSD symptoms and many presentations of psychosis. However, a good elf always does their homework and I was pleased to see from the original study protocol (de Bont et al., 2013) that the authors did look at psychotic symptoms as an outcome and plan to look at the phenomenological links between trauma exposure, PTSD and psychosis. I presume that this data is in the pipeline.

Comment

This is an exciting study, which I hope will set the wheels in motion for improving access to effective, evidence-based psychological treatments for the one in eight people with psychosis who have comorbid PTSD. In my experience this is a huge gap in service provision.

I also eagerly anticipate data regarding the impact of trauma-focused treatments on psychotic symptoms as this could be of great interest in further understanding the links between PTSD symptomology and psychosis.

Links

Primary paper

van den Berg, D.P.G, de Bont, P.A.J.M, van der Vleugel, B.M., de Roos, C., de Jongh, A., Van Minnen, A., van der Gaag, M. (2015). Prolonged Esposure vs Eye Movement Desensitization and Reprocessing vs Waiting List for Posttraumatic Stress Disorder in Patients With a Psychotic Disorder: A Randomized Clinical Trial. JAMA Psychiatry, 72:3. [PubMed abstract]

Other references

de Bont P.A., van den Berg D.P., van der Vleugel B.M., et al. (2013) A multi-site single blind clinical study to compare the effects of prolonged exposure, eye movement desensitization and reprocessing and waiting list on patients with a current diagnosis of psychosis and co morbid post traumatic stress disorder: study protocol for the randomized controlled trial Treating Trauma in Psychosis (study protocol). Trials, 14: 151.

Foa E.B., Hembree E.A., Rothbaum B.O., (2007). Prolonged Exposure Therapy for PTSD: Emotional Processing of Traumatic Experiences: Therapist Guide. Oxford, England: Oxford University Press.

Shapiro F. (2001). Eye Movement Desensitization and Reprocessing (EMDR): Basic Principles, Protocols, and Procedures. New York, NY: Guilford Press.