The effect of Eye Movement Desensitization and Reprocessing on Psychosis: A multiple baseline study.

Psychosis is characterized by delusions, hallucinations, disorganization and
catatonic behavior (American Psychiatric Association, 1994). It is perceived as
a severe disorder and seen as invalidating and stigmatizing (Dinos, Stevens,
Serfaty, Weich, & King, 2004). Only about 16-37% of people suffering from
schizophrenia fully recover. For other psychotic disorders, rates are somewhat
higher (Harrison et al., 2001; Phrenos, 2010). Since the impact of psychosis is
severe and results in high costs for both patients and their family, and
society, more effective therapeutic interventions are needed.
Trauma and psychosis are closely related (Morrison, Frame & Larkin, 2003). Of
people with psychosis, 50 to 98% report having been exposed to one or more
traumatic events in their life (Aas, Djurovic, Athanasiu, Steen, Agartz,
Lorentzen, et al., 2012; Frueh, Knapp, Cusack, Grubaugh, Sauvageot, Cousins, et
al., 2005; Goodman, Rosenberg, Mueser, Drake, 1997; Heins, Simons, Lataster,
Pfeifer, Versmissen, Lardinois, et al., 2011; Kilcommons & Morrison, 2005;
review by Read, van Os, Morrisson, & Ross, 2005). Exposure to traumatic events
plays an important role in the etiology of psychosis (Aas, Djurovic, Athanasiu,
Steen, Agartz, Lorentzen, et al., 2012; Heins et al., 2011; Goodman, Rosenberg,
Mueser, Drake, 1997; Morrison, Frame & Larkin, 2003; Read, van Os, Morrisson, &
Ross, 2005; Wigman, van Winkel, Ormel, Verhulst, van Os, & Vollebergh, 2012).
More severe trauma exposure, inflicted with more intention to harm, has been
found to be related to more severe symptoms and a worse outcome (Arseneault,
Cannon, Fisher, Polanczyk, Moffitt, Caspi, 2011; Bebbington, Brugha, Brugha,
Singleton, Farrell, Jenkins, et al., 2004; Bentall, Wickham, Shevlin & Varese,
2007; Galletly, Van Hooff, & McFarlane, 2011; Heins et al., 2011; Janssen et
al., 2004; review by Read, van Os, Morrison, & Ross, 2005; Shevlin, Houston,
Dorahy & Adamson, 2008). Different types of exposure to traumatic events are
associated with different psychotic symptoms (Bentall, Wickham, Shevlin &
Varese, 2007; Kilcommons & Morrison, 2005). The content of positive symptoms
seems related to specific experiences of trauma in people*s lives (Bentall,
Wickham, Shevlin & Varese, 2007; Falukozi & Addington, 2012; Hardy, Fowler,
Freeman, Smith, Steel, Evans, et al., 2005; Kilcommons & Morrison, 2005; review
by Morrison, Frame & Larkin, 2003). In many cases, psychosis develops after a
life event that induces stress or strong emotions (review by Freeman & Garety,
2003; Romme & Escher, 1989; Slade, 1972, 1973). The experience of symptoms of
psychosis and experiences during treatment can also be traumatizing in itself
(Bendall, McGory & Krstev, 2006; Shaw, McFarlane & Bookless, 1997; Frueh et
al., 2005). Positive symptoms (hallucinations and delusions) in particular seem
to have a large impact (Bendall, McGory & Krstev, 2006).
Many clinicians do not treat the impact of traumatic events when a patient has
a psychotic disorder. Leading researchers advise clinicians to actively inquire
for traumatic experiences in patients with psychotic symptoms (Bendall,
Alvarez-Jimenez, Nelson & McGorry, 2013; Read, Hammersley, & Rudegeair, 2007;
Read, van Os, Morrisson, & Ross, 2005) and treat these when necessary (Bendall,
et al., 2013).

EMDR is among the first-choice treatments for PTSD (Trimbos, 2009). In EMDR
therapy, the current most disturbing image of a memory is evoked, which is
followed by the employment of eye movements (De Jongh & ten Broeke, 2011; De
Jongh & ten Broeke, 2009a). As a result of EMDR, an unsettling memory image
becomes less vivid and emotional, and is stored in a new way (van den Hout &
Engelhardt, 2011; De Jongh et al., 2013). Negative cognitions attached to this
memory lose credibility and opposed to this, positive cognitions become more
believable (De Jongh & ten Broeke, 2011; De Jongh & ten Broeke, 2009a).
First results on the application of EMDR for PTSD in patients with psychosis in
the Netherlands (T-TIP, treating trauma in psychosis) show positive outcomes
(van den Berg & van der Gaag, 2012; de Bont, van Minnen & De Jongh, 2013). Some
of the results indicate that psychotic symptoms, in particular hallucinations,
can improve after PTSD treatment (van den Berg & van der Gaag, 2012;
McGoldrick, Begum & Brown, 2008). Clinical experience and some research also
suggest EMDR is effective in the treatment of psychotic symptoms (van den Berg,
van der Vleugel, Staring, de Bont, & De Jongh, 2013).
Based on prior research mentioned above, EMDR seems a suitable intervention for
patients with psychotic symptoms without PTSD. Hallucinations are often related
to traumatic experiences in individuals* lives (Hardy et al., 2005). Moreover,
there are indications that EMDR can successfully be applied with a focus on
traumatic memories linked to these experiences (van den Berg et al., 2013).

This study will examine the effectiveness of EMDR in the treatment of
psychosis, in patients without PTSD. Primary objective of this study is a first
exploration of the efficacy of EMDR in the reduction of psychotic symptoms,
perceived power of voices, and negative cognitions related to voices in
patients not fulfilling the criteria of post-traumatic stress disorder (PTSD).
This study aims to contribute to the developmental model of psychosis and its
possible traumatic origin, and how EMDR could intervene. It is hypothesized
that severity of psychotic symptoms will be reduced following EMDR-treatment.
Also, it is hypothesized that negative cognitions associated with psychotic
symptoms will become less credible after treatment and perceived power of
voices will be reduced.

The current study is a multiple baseline across subjects design, the start of
treatment (EMDR-therapy) will be randomized over a baseline period.

Patients will receive a maximum of nine sessions of EMDR treatment lasting
ninety minutes each. For each patient, a case conceptualization based upon the
Two Method Approach (De Jongh & ten Broeke, 2011; De Jongh, Ten Broeke, &
Meijer, 2010), will be made, approved by both an accredited supervisor of the
Dutch EMDR Association and an expert on psychosis. After target selection, the
standard EMDR-procedure in Dutch (De Jongh & ten Broeke, 2003) adapted from
Shapiro*s work (1995), will be used. (See Background for more information on
EMDR-therapy.)

Eye Movement Desensitisation and Reprocessing is a safe and widespread
therapeutic intervention, used all over the Netherlands. First results on the
application of EMDR for PTSD in patients with psychosis in the Netherlands
(T-TIP, treating trauma in psychosis) show positive outcomes, with less risks
for clients in the treatment condition compared to the waiting list condition
(van den Berg & van der Gaag, 2012; de Bont, van Minnen & De Jongh, 2013). Some
of the results indicate that psychotic symptoms, in particular hallucinations,
can improve after PTSD treatment (van den Berg & van der Gaag, 2012;
McGoldrick, Begum & Brown, 2008). Clinical experience also suggests that EMDR
is effective in the treatment of psychotic symptoms in patients without PTSD
(van den Berg, van der Vleugel, Staring, de Bont, & De Jongh, 2013). Based on
these recent research results and insights, EMDR can be considered a safe
intervention for psychotic patients and good clinical practice for patients
with psychosis without PTSD. Based on clinical experience, it seems likely that
at least some of the patients will benefit from the therapeutic intervention in
this study.

The burden for patients in this study is acceptable. They will have to visit
the FACT-team to fill in questionnaires weekly. Filling in questionnaires will
take about 10 minutes per week for a maximum of 26 weeks (depending on baseline
length), and about 350 minutes in total. This will be combined with therapy
sessions when the treatment intervention begins and with other appointments or
activities at the location as much as possible.
It should be noted that the burden for patients in the studies mentioned before
was considerably larger than in the proposed study (de Bont, van den Berg, van
der Vleugel, de Roos, Mulder, Becker, et al. , 2013; de Bont, van Minnen & de
Jongh, 2013). Patients will be informed well before they agree to participate.
(For more information see *aanvullende opmerkingen*.)