The main objective of this project is to analyze whether EMDR therapy, as an adjuvant to usual treatment, is effective in reducing post-traumatic stress and psychotic/affective symptoms in patients with a FEP and comorbid psychological trauma associated with first hospital admission and / or previous stressful life event.

Background: The experience of psychosis and hospitalization may be highly distressing. In fact, a significant proportion of FEP patients show posttraumatic stress symptoms during their recovery, which has been conceptualized as a posttraumatic postpsychotic syndrome (PPS). Moreover, the prevalence of childhood trauma in psychotic patients is four times higher than in general population. It is currently recognized the clinical implications of trauma in psychosis, as well as the need for treatment. Eye Movement Desensitization and Reprocessing (EMDR) therapy is a well stablished trauma treatment. EMDR is an eight- phase treatment protocol that includes bilateral stimulation to desensitize the discomfort caused by traumatic memories. Initial evidence suggests that EMDR is safe, well tolerated and beneficial in chronic patients with severe mental illness and comorbid psychological trauma.

Objectives: To assess if EMDR therapy leads to: 1) reduce post-traumatic stress symptoms; 2) reduce positive, negative and affective symptoms; 3) improve overall functioning; and 4) improve quality of life.

The hypothesis of this trial is that subjects of the EMDR group will experience an overall clinical improvement after therapy and will suffer from less admissions and relapses at 12 months of follow-up.

Design:

This is a multicenter phase II rater-blinded randomized controlled trial in which 80 FEP patients and psychological trauma will be randomly assigned to EMDR (n=40) or to TAU (n=40). Patients in the EMDR condition will receive up to 20 psychotherapeutic sessions of 60 minutes,

Clinical and diagnostic variables:

1. Traumatic events will be measured by Global Assessment of Posttraumatic Stress Questionnaire, Cumulative Trauma Screening, the Impact of Event Scale-Revised, the Dissociative Experiences Scale, Childhood Trauma Questionnaire, The Holmes-Rahe Life Stress Inventory and the Dissociative Experiences Questionnaire.

2. Clinical symptomatology will be assessed by using:

   • Suicide and Drug Consumption module of the International Neuropsychiatric Interview
   • Structured Clinical Interview for Positive and Negative Syndrome Scale
   • Young's Scale for Mania Evaluation
   • Beck Depression II Questionnaire.

3. Functionality will be assessed with the Global Assessment of Functioning questionnaire.

4. Cognitive insight and adherence to the treatment will be measured using the Beck Cognitive Insight Scale and the Drug Attitude Inventory.

5. Quality of Life will be assessed with the Standardized Instrument developed by the EuroQol Group.

All variables will be measured at baseline, post-treatment and 12 months of follow-up.

Randomization procedure All patients meeting the inclusion criteria will receive the baseline (T0) assessment. After T0, participants will be assigned to the EMDR or TAU group following a biased coin procedure: (1) the first two patients will be randomly allocated to EMDR with p = 0.5, (2) the next patient will be allocated as follows: (b1) if one group already includes at least two more patients than the other group, the patient will be randomly allocated to EMDR with p = 0.8 is this is the smallest group and with p = 0.2 if it is the largest group, (b2) otherwise, we will first simulate that the patient is allocated to EMDR and calculate the sum of the between-group square standardized differences in site, age, sex, diagnosis and before the clinical trial between groups, we will then simulate that the patient is allocated to TAU and recalculate the sum, and finally randomly allocate the patient to EMDR with p = 0.8 if this was associated to the smallest sum and with p = 0.2 if not. For example, if we had already included 10 patients to the EMDR group and 8 patients to the TAU group, the 19th patient would be randomly allocated with p = 0.2 for EMDR and p = 0.8 for TAU. If he/she was allocated to TAU, for the 20th patient we would calculate the above sum of covariates after simulating that the he/she is allocated to EMDR and after simulating that he/she is allocated to TAU, and if the sum of the EMDR simulation was larger than the sum of the TAU simulation, we would randomly allocate the 20th patient with p = 0.2 for EMDR and p = 0.8 for TAU. Following this procedure, the final groups should be balanced in size and matched in site, age, sex and diagnosis. All steps of the randomization process will be automatically carried out by an independent researcher in a central location using a computer program.

Computation of sample size The study aims to assess the relative efficacy of an EMDR intervention protocol for patients with PEP versus TAU mainly in stabilization and clinical improvement - reduction of anxious, depressive, somatic and/or psychotic symptoms, among others. For this reason, the main variable used is the number of clinical relapses after the intervention, with a follow-up of up to 12 months. Taking into account previous studies, the calculation of the sample size has been calculated based on a survival analysis with the statistical package "powerSurvEpi" for R, using an alpha = 0.005 instead of 0.05 to allow correction for multiple comparisons. The number of patients required to detect a hazard ratio = 2 in a Cox regression with a statistical power of 80% and alpha = 0.005 is n = 36 per intervention group (two groups, total n = 72). According to Chambless and Hollon, a sample of this size should show clinically relevant differences. Assuming a loss percentage of approximately 10-15% of the patients in the study, it would be necessary to recruit approximately 80 patients, 40 for each branch of intervention.

Statistical analysis:

In order to be able to make the relevant comparisons, it was decided to include comparisons with a control group of healthy participants in the statistical analyses.

Dropouts and follow-up:

If a participant requires an inpatient stay due to an acute episode of a psychotic disorder during the 6-month intervention period, the patient will be excluded from the trial and considered as dropout because the hospital admission will mean the patient cannot continue with the EMDR psychotherapy during the acute phase. In the case of relapse during follow-up, patients will be maintained in the trial to obtain maximum information on the course of the illness.

Inclusion Criteria:

• age ≥16 years old
• presence of one or more traumatic events, causing symptoms associated with the trauma (Impact of Event Scale-Revised >0 and Subjective Units of Distress >5), but it is not necessary that traumatic events meet DSM-5 criteria for PTSD
• psychotic symptoms/psychiatric hospitalization will be considered a traumatic event when the criteria for a trauma-related disorder or stress factors according to DSM-V (Post-Traumatic Stress Disorder, Acute Stress Disorder, and Other Trauma-related Disorder and unspecified stress factors) are also met
• ability to read and write in Spanish.

Exclusion Criteria:

• current suicidal risk
• presence of organic brain diseases
• have received trauma-focused therapy in the past 2 years.

Clinical raters carrying out evaluations will be blind to the participants' research condition. Patients will not be blind to treatment as a sham alternative to EMDR therapy is impossible due to its use of bilateral stimulation.