Trauma-Focused Treatment in Psychosis
van den Berg, D.P.G.
2017
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van den Berg, D. P. G. (2017). Trauma-Focused Treatment in Psychosis.
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CHAPTER 4
Prolonged exposure and EMDR
for PTSD v. a PTSD waiting-list
condition: effects on symptoms of
psychosis, depression and social
functioning in patients with chronic
psychotic disorders
P.A.J. de Bont
D.P.G. van den Berg
B.M. van der Vleugel
C. de Roos
A. de Jongh
M. van der Gaag
A. van Minnen
Psychol Med. 2016:1-11.
D.P.G. van den Berg was involved in developing the study concept and design; in the management of the study; the acquisition, analysis, and interpretation of the data; and in revising the manuscript.
“I defend my family with my orange umbrella,
I'm afraid of everyone, I'm afraid of everyone.”
ABSTRACT
BACKGROUND
In patients with psychotic disorders, the effects of psychological post-traumatic stress disorder (PTSD) treatment on symptoms of psychosis, depression and social functioning are largely unknown
METHOD
In a single-blind randomized controlled trial (RCT) 155 outpatients in treatment for psychosis (61.3% schizophrenic disorder, 29% schizoaffective disorder) were randomized to eight sessions prolonged exposure (PE; n = 53) or eye movement desensitization and reprocessing (EMDR) (n = 55), or a waiting-list condition (WL, n = 47) for treatment of their co-morbid PTSD. Measures were performed on (1) psychosis: severity of delusions (PSYRATS-DRS), paranoid thoughts (GPTS), auditory verbal hallucinations (PSYRATS-AHRS), and remission from psychotic disorder (SCI-SRPANSS); (2) depression (BDI-II); (3) social functioning (PSP). Outcomes were compared at baseline, post-treatment, 6-month follow-up and over all data points.
RESULTS
Compared to WL, PE and EMDR showed a significantly greater decrease of paranoid thoughts at post-treatment and over time; for PE this result was maintained at 6-month follow-up. In PE and EMDR more patients remitted from schizophrenia at post-treatment and over time (PE). Moreover, PE was significantly associated with a greater reduction of depression at post-treatment and at 6-month follow-up. Auditory verbal hallucinations and social functioning remained unchanged.
CONCLUSIONS
INTRODUCTION
Prolonged Exposure (PE) and Eye Movement Desensitization and Reprocessing (EMDR) therapy show good results in the treatment of post-traumatic stress disorder (PTSD).1 Also, in various PTSD patient populations, PE and EMDR have shown positive secondary effects on several co-morbid conditions2 albeit the secondary effects are more extensively investigated for PE (for a review see3) than for EMDR. Among the positive secondary PTSD treatment effects are clinically relevant reductions of symptoms of depression,2-4 and for PE, an increase in social functioning.4
In patients with psychotic disorders, PTSD is a prevalent condition (12.4%)5 and in patients with PTSD the likelihood of endorsing symptoms of psychosis is increased (odds ratio 3.55, 95% confidence interval 2.74–4.55).6 However, in both clinical practice and studies, patients with the combination of PTSD and psychosis have been largely excluded from trauma-focused treatments.7,8 This exclusion is mainly due to the widespread belief that treatment of PTSD in patients with psychotic disorders is harmful and will result in an exacerbation of symptoms associated with the disorder.7,9 Recently this belief has been examined in three feasibility studies with psychotic individuals.10-12 These studies reported promising neutral to positive results of PTSD treatment on symptoms associated with psychosis, depression and social function. Four other studies examined mixed severe mental illness (SMI) samples analysing outcomes in psychotic and non-psychotic individuals as one group.13-16 Therefore these studies can only provide tentative evidence about the effects of PTSD treatment in psychotic individuals. Particularly, the SMI studies’ results showed that PTSD treatment had no negative effects on psychosis, depression or functioning; indeed some positive effects were found for depression and social functioning. Therefore, on the basis of all these studies we now assume that the effects of PTSD treatment in patients with psychotic disorders are similar to those found in non-psychotic patient groups, i.e. PTSD treatment reduces co-morbid symptoms instead of aggravates them, including symptoms of psychosis,11,12 depression,11,13,14 and social functioning.14
our hypothesis is that PE and EMDR will similarly reduce co-morbid depression and increase social functioning in patients with psychotic disorders. Based on indications from a few pilot studies in PTSD patients with psychosis, we specifically hypothesize that both psychological PTSD treatments will reduce symptoms of psychosis.
METHOD
This study is part of the RCT ‘Treating Trauma in Psychosis’ (TTIP). Our design paper described the trial’s primary to quaternary objectives, inclusion and exclusion criteria, recruitment, CONSORT chart, measurement procedures, instruments, intervention conditions and statistical procedures.17
The primary outcome paper of the RCT describes the safety and efficacy of PTSD treatment for patients with psychotic disorders and provides details on patient flow, sample characteristics, safety, control procedures, blinding, treatment protocols, temporary restrictions imposed on treatment as usual (TAU; including medication), integrity checks, early completion, completers, drop-outs, serious adverse events, and medical ethical reports.18 Therefore, only a brief description of the trial is presented below.
Design
This study is a single-blind RCT with three arms [PE, EMDR, and waiting list (WL)] and is registered at Current Controlled Trials (ISRCTN 79584912). The design was approved by the Medical Ethics Committee of the VU University Medical Center (NL: 36649.029.12).
Participants
patients were excluded because of severe suicidality. In addition, eight patients were excluded on the basis of our criterion that within 2 months prior to the study no changes in medication (mood regulators, antipsychotics) were allowed. Recruitment led to the inclusion and randomization of 155 participants with various and severe co-morbid conditions, thereby strengthening the study’s generalizability23 and clinical relevance.24 None of the 155 participants received trauma-focused treatment in regular care, i.e. TAU.
Measures
Psychosis was extensively measured with three different tools:
(1) The Psychotic Symptom Rating Scale interview (PSYRATS)25 assessed the severity of delusions (Delusion Rating Scale; DRS) and auditory hallucinations (Auditory Hallucinations Rating Scale; AHRS).
(2) The Green Paranoid Thoughts Scale (GPTS)26 is a self-report scale and assessed the severity of paranoid thoughts.
(3) The Structured Clinical Interview for Symptoms of Remission27,28 for the Positive and Negative Syndrome Scale (SCI-SR-PANSS)29 assessed remission of psychotic symptoms, based on eight symptoms of the PANSS. Each participant was interviewed for functional status on delusions, unusual content of thought, hallucinations and apathy. Scores on conceptual disorganization, lack of spontaneity, blunted affect and posturing were based on clinical observation. Note that we assessed all 155 psychotic participants and not just those with a diagnosis of schizophrenia for whom the SCI-SR-PANSS was originally designed. Individuals with no functional interference of any SCI-PANSS symptom are rated ‘in remission’. Individuals with at least one of the eight symptoms functionally interfering are rated ‘not in remission’. We omitted the 6-month-span remission criterion27 and, as in the majority of remission studies,30 only used the symptom severity criterion.
Procedure
Demographic characteristics of the participants were recorded at baseline. All secondary outcome measures were assessed at baseline, post-treatment and at the 6-month follow-up. Blinded assessors performed the measurements throughout the study.
After screening and inclusion, participants completed a baseline assessment designed to meet all needs related to the objectives of the TTIP trial17 including assessments on secondary outcomes. Then, 155 consenting individuals were randomly assigned to either eight weekly 90-min sessions of PE (n = 53) or EMDR (n = 55) for their PTSD, or to the WL condition (n = 47). At the 6-month follow-up assessment individuals in the WL condition were offered treatment of choice. All participants received a financial compensation of €25 for each assessment.
Treatment
The therapists provided patients in the WL condition with information about PTSD and an appointment after the follow-up period to discuss the patient’s choices for PTSD treatment. Patients in the treatment conditions received eight weekly scheduled treatment sessions, following official PTSD treatment manuals. Details of the protocols for PE33 and EMDR34 are already published.18
Multidisciplinary Assertive Community Treatment is TAU for patients with psychosis in The Netherlands. Teams in the 13 participating mental health services delivered comparable TAU in all three conditions to the 155 participants for their psychotic disorders. In this study TAU consisted of medication, and treatment and/or support by therapists, caseworkers, nurses and/or coaches; all this with the exclusion of trauma-focused interventions.
Training, supervision and treatment adherence
The training and supervision of therapists was aimed at strictly and solely applying the experimental procedures (PE and EMDR therapy protocols, and WL) in order to prevent secondary outcomes being dependent on unsanctioned interventions and deviations.35 ‘Secondary’ symptoms that might possibly emerge during the sessions, such as auditory verbal hallucinations (AVHs) or delusions, which may or may not be trauma related in origin,36,37 were not to be targeted directly.
and 97.1% of the EMDR sessions, indicating that the therapists had optimal fidelity concerning the treatment protocols.
Statistical analysis
Analyses were conducted with SPSS v. 20 (IBM Corp., USA). Baseline differences on demographic and clinical variables were analysed using analysis of variance, χ2 test and t test. Treatment outcome was compared across the three conditions at post-treatment, at 6-month follow-up and over time (i.e. over all data points), using interaction effects. Linear mixed model (LMM) intention-to-treat (ITT) analyses were conducted on the continuous variables paranoid thoughts (GPTS), depression (BDI-II) and social functioning (PSP). Baseline scores were included as covariate, time as categorical variable, and treatment condition as a fixed effect. The intercept was treated as a random effect. Between-group effect sizes (PE v. WL and EMDR v. WL) were computed according to Cohen’s d38 using estimated data from the LMM procedure.
Logistic generalized estimating equations (GEE)39 with exchangeable correlation structure ITT analysis was used to examine effects on the dichotomous variable remission from psychosis (SCI-SRPANSS).
Unfortunately, not all data from the AHRS and DRS were optimally suited for LMM analyses. Both interviews start with a dichotomous question on the presence or absence of symptoms (AVHs and delusion, respectively), forcing us to delete all observations from non-symptomatic individuals from the LMM analyses. Because GPTS continuous data of all 155 participants were available, the LMM of the DRS data was omitted. However, because an alternative instrument measuring hallucinations was lacking, we used the hallucinations AHRS continuous scores in the LMM analysis (from individuals who were symptomatic at any time point).
Sensitivity analysis was performed with completers (n = 113) and ITT analyses with the last observation carried forward (LOCF) (n = 155), with missing data conservatively replaced with a negative value, i.e. no loss of symptom.
Ethical standards
TABLE 1 · Baseline demographic, clinical and secondary symptom characteristics
Age (years), mean (S.D.) Gender, n
Male Female Psychosis
Chlorpromazine drug dose equivalents, mean (S.D.)a Duration psychosis in years, mean (S.D.)
MINI Plus classifications, n (%) Schizophrenia
Schizoaffective disorder Remaining psychotic disorders Mood disorders with psychotic features
PTSD
CAPS, mean (S.D.)
Duration PTSD in years, mean (S.D.) Suicidality, n (%)
Suicide attempt (ever)
MINI-Plus current medium or high suicide risk
Secondary outcome DRS delusions, mean (S.D.) GPTS paranoid/referential thoughts, mean (S.D.)
AHRS auditory verbal hallucinations, mean (S.D.)
SCI-SR-PANSS no remission from psychotic disorder, n (%) BDI-II depression, mean (S.D.) PSP functioning, mean (S.D.) EMDR (n = 55) 40.4 (11.3) 25 30 253.2 (250.5) 18.2 (11.7) 34 (61.8) 15 (27.3) 3 (5.5) 3 (5.4) 72.1 (17.6) 21.1 (13.9) 33 (60.0) 23 (41.8) 8.7 (8.0) 82.7 (29.2) 12.04 (14.8) 30 (54.5) 28.2 (11.6) 51.0 (12.6) Total sample (n = 155) 41.2 (10.5) 71 84 243.6 (224.2) 17.7 (11.8) 95 (61.3) 45 (29.0) 5 (3.2) 10 (6.4) 69.9 (16.2) 21.0 (13.5) 94 (60.6) 70 (45.2) 9.5 (8.0) 85.1 (32.8) 11.02 (14.3) 86 (55.5) 29.6 (11.7) 51.1 (11.7) 42.6 (10.3) 23 30 227.3 (187.9) 18.9 (12.8) 31 (58.5) 17 (32.1) 1 (1.9) 4 (7.6) 69.6 (14.9) 22.8 (13.6) 33 (62.3) 27 (50.9) 9.1 (7.7) 88.8 (37.6) 10.64 (14.1) 38 (52.8) 30.9 (11.4) 50.9 (12.7) PE (n = 53) Characteristic 40.3 (9.7) 23 24 250.7 (232.8) 15.7 (10.5) 30 (63.8) 13 (27.7) 1 (2.1) 3 (6.4) 68.1 (15.9) 18.95 (12.9) 28 (59.6) 20 (41.6) 10.7 (8.4) 83.8 (31.4) 10.26 (14.2) 28 (59.6) 29.7 (12.4) 51.5 (9.6) WL (n = 47)
AHRS, Auditory Hallucination Rating Scale; BDI-II, Beck Depression Inventory – II; CAPS, Clinician-Administered PTSD Scale; DRS, Delusion Rating Scale; EMDR, eye movement desensitization and reprocessing; GPTS, Green Paranoid Thought Scale; MINI Plus, MINI International Neuropsychiatric Interview-Plus; PSP, Personal and Social Performance scale; PTSD, post-traumatic stress disorder; SCI-SR-PANSS, Structured Clinical Interview for Symptoms of Remission for the Positive and Negative Syndrome Scale; S.D., standard deviation.
RESULTS
ITT analyses
Details on the flow and baseline characteristics of the participants are published elsewhere18 and are available online (CHAPTER 3). TABLE 1 shows the baseline characteristics of the secondary symptoms per condition and in total. The 61.9% individuals with active delusions and the 40.0% individuals with active hallucinations exhibited medium severe symptom intensity. The mean level of paranoid thoughts was relatively high40 considering our sample’s heterogeneous mix of psychotic disorders. Of all individuals, 55.5% presented current core symptoms of schizophrenia, signalling impaired wellbeing and functioning. The baseline average depression score of the entire group scaled moderate to severe;31 prominent were suicide attempts in the past (60.6%) and current medium to high suicidal risks (45.2%). The baseline mean score on personal and social performance indicated moderate to serious impairment of social, occupational or school functioning.32 There were no differences between the conditions on any variables at baseline.
Fig. 1 summarizes the major findings of the study by presenting the observed trajectories
of outcomes for each of the variables in the study.
TABLE 2 presents estimated marginal means produced by the LMM procedure, pre-post
effect sizes and LMM outcomes, based on ITT between-group analyses comparing PE and EMDR to WL. Compared to WL, PE and EMDR showed a significantly greater decrease of paranoid thoughts at post-treatment and over time; this was maintained at 6-month follow-up only for PE.
EMDR and WL yielded similar results in reducing depression, whereas PE was superior to WL at posttreatment, follow-up and over time, and also superior to EMDR (not presented in TABLE 2; at 6-month follow-up the between-group effect size PE v. EMDR
= 0.48, p = 0.026, and over time p = 0.036).
PE, EMDR and WL did not differ on AVHs and social functioning.
LMM sensitivity analyses of completers (n = 113) and of ITT-LOCF yielded similar results.
TABLE 3 presents GEE ITT between-group analyses of remission status, comparing PE
LOCF sensitivity analysis showed significantly more remission for PE only at post-treatment. As was previously published (for details see18) there were no differences between conditions in additional support or nontrauma-focused psychotherapy (e.g. cognitive behavior therapy) or changes in the use of medication. Moreover, and importantly, no participants received additional trauma-focused treatments.
70 60 50 40 30 20 10 0
Baseline Posttreatment 6-mo Follow-up
60 50 40 30 20 10 0
Baseline Posttreatment 6-mo Follow-up
AHRS, Auditory Hallucination Rating Scale; BDI-II, Beck Depression Inventory – II; CAPS, Clinician-Administered PTSD Scale; GPTS, Green Paranoid Thoughts Scale; SCI-SRPANSS, Structured Clinical Interview for Symptoms of Remission for the Positive and Negative Syndrome Scale.
a Mean scores are based on individuals who were actively hallucinating at baseline and/or post-treatment and/or follow-up.
Percentage of individuals in remissions | SCI-SR_PANSS
Quality of personal and social functioning | PSP mean total (range 1-100)
30 25 20 15 10 5 0 100 90 80 70 60 50 40 30 20 10 0
Baseline Posttreatment 6-mo Follow-up
Baseline Posttreatment 6-mo Follow-up
40 35 30 25 20 15 10 5 0
Baseline Posttreatment 6-mo Follow-up
Severity of paranoid- referential thinking | GPTS mean total (range 32-160) Severity of voice hearinga | AHRS mean total (range 0-55)
Severity of depression symptoms | BDI-II-mean total (range 0-63)
PE
EMDR
WL
TABLE 2 · Es tim at ed s eco nd ar y s ev er ity o ut co m es a s a f un ct io n o f t re at m en t g ro up (n=155) in ten tio n t o t re at GPTS a, mean [ n] (95% CI) Baseline scor e [ n] Between-gr oup ef fect size b LMM c AHRS d, mean [ n] (95% CI) Baseline scor e [ n] Between-gr oup ef fect size LMM BDI-II, mean [ n] (95% CI) Baseline scor e [ n] Between-gr oup ef fect size LMM PSP , mean [ n] (95% CI) Baseline scor e Between-gr oup ef fect size LMM 67.3 [47] (60.1-74.5) 88.8 [53] 0.62 t200 = -2.86 (.005) 18.8 [22] (13.2-24.4) 21.7 [26] 0.56 t101 = -1.26 (.212) 18.3 [47] (15.2-21.4) 30.9 [53] 0.78 t175 = -3.61 (<.001) 52.4 [47] (49.1–55.7) 50.9 [53] -0.17 e t223 = 0.81 (.421) PE 68.0 [44] (60.6-75.5) 82.7 [55] 0.59 t200 = -2.68 (.008) 16.8 [23] (11.2-22.3) 24.5 [27] 0.40 t102 = -1.74 (.085) 22.2 [44] (19.0-25.4) 28.2 [55] 0.42 t174 = -1.91 (.058) 53.5 [44] (50.1–56.9) 51.0 [55] -0.27 t223 = 1.25 (.214) EMDR 82.7 [39] (74.9-90.6) 83.8 [47] 24.2 [17] (17.8-30.6) 23.0 [21] 26.7 [39] (23.3-30.0) 29.7 [47] 50.4 [39] (46.8–54.0) 51.5 [47] WL
PE>WL EMDR>WL n.s. PE>WL n.s
Significant differ
ences PE v. EMDR v. WL ( p<.05) 65.0 [45] (57.7-72.3) 88.8 [53] 0.54 t202 = -2.46. (.015) 22.5 [20] (16.6-28.4) 21.7 [26] -0.42 t102 = .1.31 (.195) 17.8 [45] (14.6-20.9) 30.9 [53] 0.64 t177 = -2.92 (.004) 52.6 [45] (49.3–56.0) 50.9 [53] -0.31 t225 = 1.42 (.156) PE 70.2 [43] (62.7-77.7) 82.7 [55] 0.33 t201 = -1.48 (.140) 16.1 [22] (10.4-21.7) 24.5 [27] 0.06 t101 = .-0.18 (.857) 22.9 [43] (19.7-26.2) 28.2 [55] 0.15 t176 = -.69 (.493) 51.9 [43] (48.5–55.4) 51.0 [55] -0.25 t224 = 1.13 (.260) EMDR PE >WL t129 = -3.03 (.003) n.s. t = -1.10366 (.274) PE> WL t133 = -3.52 (.001) n.s. t133 = 1.34 (.183) PE EMDR>WL t129 = -2.38 (.019) t = 0.02366 (.981) PE>EMDR t133 = -1.41 (.161) t132 = 1.43 (.155) EMDR 78.3 [39] (70.5-86.2) 83.8 [47] 16.8 [18] (10.6-23.1) 23.0 [21] 24.5 [39] (21.2-27.9) 29.7 [47] 49.1 [39] (45.5–52.7) 51.5 [47] WL
PE>WL n.s. PE>WL PE>EMDR n.s.
Significant differ
ences PE v. EMDR v. WL ( p<.05) AHRS, A udi to ry H al lucin at io n R at in g S ca le; B D I-II, B ec k D ep res sio n I nv en to ry-II; CAPS, C linici an-A dmini ster ed PT SD S ca le; CI, co nfiden ce in ter va l; EMD R, e ye m ov em en t des en sit iza tio n a nd r ep ro ces sin g; GPT S, G re en P ara no id Th oug ht S ca le; LMM, L in ea r M ix ed M ode l a na lys es; n.s., n ot sig nific an t; P E, p ro lo ng ed exp os ur e; PS P, P er so na l a nd S oci al P er fo rm an ce s ca le; S.D ., s ta nd ar d de vi at io n; WL, wa itin g li st. a D at a r efle ct es tim at ed m ar gin al m ea ns (95% CI) f ro m t he LMM a na lys es. b B et w een-g ro up eff ec t sizes co ncer n t he diff er en ces b et w een t he t re at m en t co ndi tio ns P E a nd EMD R v . WL co ndi tio n a t t he diff er en t t im e p oin ts. Eff ec t size , C oh en ’s d i s c al cul at ed usin g t he diff er en ce o f es tim at ed m ar gin al m ea ns (LMM) di vide d b y t he a vera ge S.D .. c LMM o ut co m e r es ul ts (t va lues a nd p va lues) co ncer n t he co m pa ris on o f P E a nd EMD R v . WL. R es ul ts o f co m pa ris on s o f P E v . EMD R a re n ot in clude d in t hi s TABLE (a va ila ble fro m fir st a ut ho r). d N ot e h er e t ha t LMM wa s p er fo rm ed o n a s ubs am ple o f ac tiv ely (i .e. p re , p os t a nd/o r f ol lo w-u p) h al lucin at in g in di vid ua ls. e A s o pp os ed t o t he o th er in str um en ts hig her PS P m ea n s co res r ep res en t im pr ov em en t in ste ad o f w or senin g; a n ega tiv e eff ec t size h er e m ea ns t ha t t he b et w een-g ro up eff ec t i s posi tiv e f or t he exp er im en ta l co ndi tio n. Post-tr eatment 6-month Follow-up
Over time Significant dif
fer ences PE v. EMDR v. WL ( p<.05) - T
ABLE CONTINUES ON NEXT P
-TABLE 2 · Es tim at ed s eco nd ar y s ev er ity o ut co m es a s a f un ct io n o f t re at m en t g ro up (n=155) in ten tio n t o t re at GPTS a, mean [ n] (95% CI) Baseline scor e [ n] Between-gr oup ef fect size b LMM c AHRS d, mean [ n] (95% CI) Baseline scor e [ n] Between-gr oup ef fect size LMM BDI-II, mean [ n] (95% CI) Baseline scor e [ n] Between-gr oup ef fect size LMM PSP , mean [ n] (95% CI) Baseline scor e Between-gr oup ef fect size LMM 67.3 [47] (60.1-74.5) 88.8 [53] 0.62 t200 = -2.86 (.005) 18.8 [22] (13.2-24.4) 21.7 [26] 0.56 t101 = -1.26 (.212) 18.3 [47] (15.2-21.4) 30.9 [53] 0.78 t175 = -3.61 (<.001) 52.4 [47] (49.1–55.7) 50.9 [53] -0.17 e t223 = 0.81 (.421) PE 68.0 [44] (60.6-75.5) 82.7 [55] 0.59 t200 = -2.68 (.008) 16.8 [23] (11.2-22.3) 24.5 [27] 0.40 t102 = -1.74 (.085) 22.2 [44] (19.0-25.4) 28.2 [55] 0.42 t174 = -1.91 (.058) 53.5 [44] (50.1–56.9) 51.0 [55] -0.27 t223 = 1.25 (.214) EMDR 82.7 [39] (74.9-90.6) 83.8 [47] 24.2 [17] (17.8-30.6) 23.0 [21] 26.7 [39] (23.3-30.0) 29.7 [47] 50.4 [39] (46.8–54.0) 51.5 [47] WL
PE>WL EMDR>WL n.s. PE>WL n.s
Significant differ
ences PE v. EMDR v. WL ( p<.05) 65.0 [45] (57.7-72.3) 88.8 [53] 0.54 t202 = -2.46. (.015) 22.5 [20] (16.6-28.4) 21.7 [26] -0.42 t102 = .1.31 (.195) 17.8 [45] (14.6-20.9) 30.9 [53] 0.64 t177 = -2.92 (.004) 52.6 [45] (49.3–56.0) 50.9 [53] -0.31 t225 = 1.42 (.156) PE 70.2 [43] (62.7-77.7) 82.7 [55] 0.33 t201 = -1.48 (.140) 16.1 [22] (10.4-21.7) 24.5 [27] 0.06 t101 = .-0.18 (.857) 22.9 [43] (19.7-26.2) 28.2 [55] 0.15 t176 = -.69 (.493) 51.9 [43] (48.5–55.4) 51.0 [55] -0.25 t224 = 1.13 (.260) EMDR PE >WL t129 = -3.03 (.003) n.s. t = -1.10366 (.274) PE> WL t133 = -3.52 (.001) n.s. t133 = 1.34 (.183) PE EMDR>WL t129 = -2.38 (.019) t = 0.02366 (.981) PE>EMDR t133 = -1.41 (.161) t132 = 1.43 (.155) EMDR 78.3 [39] (70.5-86.2) 83.8 [47] 16.8 [18] (10.6-23.1) 23.0 [21] 24.5 [39] (21.2-27.9) 29.7 [47] 49.1 [39] (45.5–52.7) 51.5 [47] WL
PE>WL n.s. PE>WL PE>EMDR n.s.
Significant differ
ences PE v. EMDR v. WL ( p<.05) AHRS, A udi to ry H al lucin at io n R at in g S ca le; B D I-II, B ec k D ep res sio n I nv en to ry-II; CAPS, C linici an-A dmini ster ed PT SD S ca le; CI, co nfiden ce in ter va l; EMD R, e ye m ov em en t des en sit iza tio n a nd r ep ro ces sin g; GPT S, G re en P ara no id Th oug ht S ca le; LMM, L in ea r M ix ed M ode l a na lys es; n.s., n ot sig nific an t; P E, p ro lo ng ed exp os ur e; PS P, P er so na l a nd S oci al P er fo rm an ce s ca le; S.D ., s ta nd ar d de vi at io n; WL, wa itin g li st. a D at a r efle ct es tim at ed m ar gin al m ea ns (95% CI) f ro m t he LMM a na lys es. b B et w een-g ro up eff ec t sizes co ncer n t he diff er en ces b et w een t he t re at m en t co ndi tio ns P E a nd EMD R v . WL co ndi tio n a t t he diff er en t t im e p oin ts. Eff ec t size , C oh en ’s d i s c al cul at ed usin g t he diff er en ce o f es tim at ed m ar gin al m ea ns (LMM) di vide d b y t he a vera ge S.D .. c LMM o ut co m e r es ul ts (t va lues a nd p va lues) co ncer n t he co m pa ris on o f P E a nd EMD R v . WL. R es ul ts o f co m pa ris on s o f P E v . EMD R a re n ot in clude d in t hi s TABLE (a va ila ble fro m fir st a ut ho r). d N ot e h er e t ha t LMM wa s p er fo rm ed o n a s ubs am ple o f ac tiv ely (i .e. p re , p os t a nd/o r f ol lo w-u p) h al lucin at in g in di vid ua ls. e A s o pp os ed t o t he o th er in str um en ts hig her PS P m ea n s co res r ep res en t im pr ov em en t in ste ad o f w or senin g; a n ega tiv e eff ec t size h er e m ea ns t ha t t he b et w een-g ro up eff ec t i s posi tiv e f or t he exp er im en ta l co ndi tio n. Post-tr eatment 6-month Follow-up
Over time Significant dif
fer ences PE v. EMDR v. WL ( p<.05) TABLE 2 · Es tim at ed s eco nd ar y s ev er ity o ut co m es a s a f un ct io n o f t re at m en t g ro up (n=155) in ten tio n t o t re at GPTS a, mean [ n] (95% CI) Baseline scor e [ n] Between-gr oup ef fect size b LMM c AHRS d, mean [ n] (95% CI) Baseline scor e [ n] Between-gr oup ef fect size LMM BDI-II, mean [ n] (95% CI) Baseline scor e [ n] Between-gr oup ef fect size LMM PSP , mean [ n] (95% CI) Baseline scor e Between-gr oup ef fect size LMM 67.3 [47] (60.1-74.5) 88.8 [53] 0.62 t200 = -2.86 (.005) 18.8 [22] (13.2-24.4) 21.7 [26] 0.56 t101 = -1.26 (.212) 18.3 [47] (15.2-21.4) 30.9 [53] 0.78 t175 = -3.61 (<.001) 52.4 [47] (49.1–55.7) 50.9 [53] -0.17 e t223 = 0.81 (.421) PE 68.0 [44] (60.6-75.5) 82.7 [55] 0.59 t200 = -2.68 (.008) 16.8 [23] (11.2-22.3) 24.5 [27] 0.40 t102 = -1.74 (.085) 22.2 [44] (19.0-25.4) 28.2 [55] 0.42 t174 = -1.91 (.058) 53.5 [44] (50.1–56.9) 51.0 [55] -0.27 t223 = 1.25 (.214) EMDR 82.7 [39] (74.9-90.6) 83.8 [47] 24.2 [17] (17.8-30.6) 23.0 [21] 26.7 [39] (23.3-30.0) 29.7 [47] 50.4 [39] (46.8–54.0) 51.5 [47] WL
PE>WL EMDR>WL n.s. PE>WL n.s
Significant differ
ences PE v. EMDR v. WL ( p<.05) 65.0 [45] (57.7-72.3) 88.8 [53] 0.54 t202 = -2.46. (.015) 22.5 [20] (16.6-28.4) 21.7 [26] -0.42 t102 = .1.31 (.195) 17.8 [45] (14.6-20.9) 30.9 [53] 0.64 t177 = -2.92 (.004) 52.6 [45] (49.3–56.0) 50.9 [53] -0.31 t225 = 1.42 (.156) PE 70.2 [43] (62.7-77.7) 82.7 [55] 0.33 t201 = -1.48 (.140) 16.1 [22] (10.4-21.7) 24.5 [27] 0.06 t101 = .-0.18 (.857) 22.9 [43] (19.7-26.2) 28.2 [55] 0.15 t176 = -.69 (.493) 51.9 [43] (48.5–55.4) 51.0 [55] -0.25 t224 = 1.13 (.260) EMDR PE >WL t129 = -3.03 (.003) n.s. t = -1.10366 (.274) PE> WL t133 = -3.52 (.001) n.s. t133 = 1.34 (.183) PE EMDR>WL t129 = -2.38 (.019) t = 0.02366 (.981) PE>EMDR t133 = -1.41 (.161) t132 = 1.43 (.155) EMDR 78.3 [39] (70.5-86.2) 83.8 [47] 16.8 [18] (10.6-23.1) 23.0 [21] 24.5 [39] (21.2-27.9) 29.7 [47] 49.1 [39] (45.5–52.7) 51.5 [47] WL
PE>WL n.s. PE>WL PE>EMDR n.s.
Significant differ
ences PE v. EMDR v. WL ( p<.05) AHRS, A udi to ry H al lucin at io n R at in g S ca le; B D I-II, B ec k D ep res sio n I nv en to ry-II; CAPS, C linici an-A dmini ster ed PT SD S ca le; CI, co nfiden ce in ter va l; EMD R, e ye m ov em en t des en sit iza tio n a nd r ep ro ces sin g; GPT S, G re en P ara no id Th oug ht S ca le; LMM, L in ea r M ix ed M ode l a na lys es; n.s., n ot sig nific an t; P E, p ro lo ng ed exp os ur e; PS P, P er so na l a nd S oci al P er fo rm an ce s ca le; S.D ., s ta nd ar d de vi at io n; WL, wa itin g li st. a D at a r efle ct es tim at ed m ar gin al m ea ns (95% CI) f ro m t he LMM a na lys es. b B et w een-g ro up eff ec t sizes co ncer n t he diff er en ces b et w een t he t re at m en t co ndi tio ns P E a nd EMD R v . WL co ndi tio n a t t he diff er en t t im e p oin ts. Eff ec t size , C oh en ’s d i s c al cul at ed usin g t he diff er en ce o f es tim at ed m ar gin al m ea ns (LMM) di vide d b y t he a vera ge S.D .. c LMM o ut co m e r es ul ts (t va lues a nd p va lues) co ncer n t he co m pa ris on o f P E a nd EMD R v . WL. R es ul ts o f co m pa ris on s o f P E v . EMD R a re n ot in clude d in t hi s TABLE (a va ila ble fro m fir st a ut ho r). d N ot e h er e t ha t LMM wa s p er fo rm ed o n a s ubs am ple o f ac tiv ely (i .e. p re , p os t a nd/o r f ol lo w-u p) h al lucin at in g in di vid ua ls. e A s o pp os ed t o t he o th er in str um en ts hig her PS P m ea n s co res r ep res en t im pr ov em en t in ste ad o f w or senin g; a n ega tiv e eff ec t size h er e m ea ns t ha t t he b et w een-g ro up eff ec t i s posi tiv e f or t he exp er im en ta l co ndi tio n. Post-tr eatment 6-month Follow-up
Over time Significant dif
TABLE 3 · St at us o n r emi ssio n f ro m psy ch ot ic di so rder s (SCI-S R-P ANSS) a s a f un ct io n o f t re at m en t g ro up a
Lost to follow up,
n Psychotic disor der , n (%) Not in r emission In r emission GEE, OR ( p value) c 28 (52.8) 25 (47.2) PE (n=53) 30 (54.5) 25 (45.5) EMDR (n=55) 28 (59.6) 19 (40.4) WL (n=47) 8 27 (69.2) 12 (30.8) WL (n=39) PE>WL EMDR>WL Significant differ
ences (p <.05) b 6 19 (40.4) 28 (59.6) 3.39 (.008) PE (n=47) 11 19 (43.2) 5 (56.8) 3.17 (.013) EMDR (n=44) 8 18 (40.0) 27 (60.0) 1.65 (.251) PE (n=45) 12 19 (44.2) 24 (55.8) 1.43 (.415) EMDR (n=43) 7 22 (55.0) 18 (45.0) WL (n=40) ns
Significant differ
ences
(p
<.05)
PE PE>WL 2.325 (.020)
Significant differ
DISCUSSION
In our group of patients with psychotic disorders, PE and EMDR therapy were superior to the WL condition in reducing psychotic symptoms. Even though symptoms of psychosis were not directly addressed in these treatments, the severity of paranoid thoughts decreased significantly and rates of remission from psychotic disorders increased. Because co-morbid PTSD worsens the course and severity of psychotic disorders,41 it is expected that reducing PTSD will attenuate psychosis. This empirical finding is in agreement with the assumed interactions between PTSD and SMI. The strong and lasting decrease in the severity of paranoid thoughts following PTSD treatment was expected and is in line with results from pilot effect studies,11,12 studies on paranoia,42,43 a comparison of paranoia and PTSD44,45 and (meta-analytical) studies linking trauma to psychosis.36,37,46,47 Also, the integrated socio-developmental-cognitive model of schizophrenia48 would predict that successful reduction of anxiety and dysfunctional cognitions resulting from PTSD treatment abates the paranoid interpretations of aberrant information processing and helps prevent or diminish psychosis. However, the result that paranoid thoughts diminished may also partly be explained by the reduction of PTSD symptoms. PTSD was found to be associated with an increased likelihood of endorsing one or more psychotic symptoms6,49 so reducing PTSD might reduce paranoia. Furthermore, notwithstanding the fact that paranoia and PTSD clearly differ from each other,50 they also share a number of features including increased arousal (e.g. hyper vigilance, poor sleep, anger) and negative cognitions (e.g. distrust in others).
severity of depression did not decline with EMDR therapy. This could be a deviant result or there might be an alternative explanation. For example, both treatments demanded considerable effort and a certain amount of courage from the patients, but the disclosure of traumatic events is much more detailed in PE. Further, PE involves a considerable amount of homework whereas EMDR does not. Perhaps the higher degree of activation in PE and a heightened sense of personal accomplishment helped to reduce depression in PE. No changes occurred in social functioning, possibly and partly due to the fact that not all traumas of our multi-trauma sample18,19 could be addressed in treatment, which may have limited social change. But an even more important factor might have been that the PSP is not very reactive to subtle changes in social function. A PSP score change reflects significant changes in one or more domains (work, friendship, etc.). Now the duration of the treatment (eight sessions) and assessment period (6-month follow-up) was very brief relative to the chronicity of patients’ behavioural and social dysfunction (mean duration of psychosis was 17.7 years). Subtle changes in social functioning might have occurred, but major changes were not to be expected in the short amount of time. So for future studies instruments suited for assessing subtle, short-term changes in social functioning or extended treatment and follow up periods using the PSP are recommended.
Generally speaking, our successful treatment of the PTSD symptoms of patients with psychosis helped reduce some of the burden of co-morbid symptoms as well. Our observations fit the network view on psychiatric disorders53 that postulates that symptoms (e.g. anxiety, voice hearing, depressed mood) fire up each other and that treatment of one symptom also benefits associated symptoms. For a long time, psychosis has been the highest ranking exclusion criterion for psychological PTSD treatment, out of fear of doing patients harm. Yet, our PTSD treatment outcome data demonstrate that together with the PTSD symptoms18 significant additional symptom relief of psychosis can be achieved by trauma-focused treatment. This also holds true for symptoms of depression (for PE).
DSM-IV schizophrenic disorders are extraordinarily varied with very unclear syndrome boundaries.54 A limitation of the current study is the relatively impaired examination of AVHs and the absence of examination of other than verbal hallucinatory experiences, especially visual hallucinations. Another limitation is that in this study we did not monitor changes in our outcome variables during and between sessions. Insight in changes occurring during treatment is important, because a possible increase of symptomatology during treatment may also be a concern of clinicians, especially after the start of the trauma-focused sessions. This concern is addressed in a recent publication by Van den Berg et al.55 The study demonstrates that in our study sample, compared to WL, the trauma-focused treatment groups were significantly associated with less symptom exacerbation and less adverse events during the treatment, including the first trauma-focused treatment sessions. Clearly all of these findings combined do not support the conventional idea that it is best clinical practice to withhold this patient group from trauma-focused therapy; on the contrary, all of these findings build a strong case that delivering PTSD treatment to patients with psychosis and PTSD deserves recognition and acceptance among clinicians and researchers.
The strengths of this study include its highly controlled design, the recruitment of patients in care for psychosis from routine clinical settings, the inclusion of patients with severe levels of co-morbidity, and the application of widely used PTSD treatment protocols. These strengths enhance the generalizability of the observed effects to patients in routine clinical practice, and add credibility to the idea that offering trauma-focused treatment to this patient group is clinically feasible.
CONCLUSIONS
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