“Why is there limited effectiveness for CBT for AVH?And how can we enhance treatment?”
Guy Dodgson, Consultant Clinical Psychologist (EIP), Northumberland Tyne and Wear NHS Foundation Trust, offers the following overview of his presentation to the Joint Special Interest in Psychosis Group on April 24 2013:
(i) A summary of evidence for the effectiveness of CBT for auditory verbal hallucinations
A recent review by McCarthy-Jones et al (submitted) concluded “the existing evidence from RCTs for the effectiveness of CBT for AVH is weak. Methodological limitations of existing studies which frequently included low statistical power, failure to employ multi dimensional outcome measures of AVH and limited amounts of session time focussing on AVHs, preclude clear conclusions being reached at to the effectiveness of CBT for AVHs”. This conclusion was reached from reviewing ten papers which reported outcomes for AVH measures. Although some of the papers found effects at the end of treatment very few studies found any evidence at follow up of effectiveness.
A review by Robson et al had looked at single case design research on CBT for AVH. This identified four files, three of which were too weak to be included in the review. This was for issues related to lack of participants, measures used and number of data points collected. Only one study was considered of sufficient robustness to be reviewed fully and this was the Fowler and Morley paper (1989). They found replications for improvements in control over hallucinations in three of five participants. However, other measures seem to show little effect.
A question at the end of the talk raised the issue of why the outcomes were so weak for AVH. McCarthy-Jones et al outlined lots of methodological weaknesses including things such as low statistical power. Other problems with research in the area is that it is difficult to secure funding for trials, certainly in comparison to drug trials where there is a powerful incentive for drug companies to invest in this area. Therefore, there has been a shortage of good, robust, well-controlled trials. However, a soon to be published German trial is methodologically sound with a high number of participants and this has shown a good affect for CBT with Psychosis so therefore the recent criticism for CBT for AVH will be refuted. However, the problems are not just with the trials and with the difficulties of funding, it is likely that the intervention is currently weak and that additional effort is required to make CBT for AVH more effective.
(ii) Why is current CBT treatment for AVH weak?
Four issues were outlined. First, voice hearing often can be the “anomalous event” that triggers a delusional system. Therefore if people are not treated quickly then voice hearing quickly becomes mixed up with delusional ideas and this becomes more difficult to treat. Secondly, Birchwood and Trower have criticised current CBT for psychosis suggesting this is simply the extension of general CBT concepts without taking into account the specificity of psychosis.. There are no specific models which really help boost the effectiveness of the approach such as the panic model developed by Clark et al. Thirdly, the treatments that do exist have been developed without reference to the academic literature about voice hearing. A review by Garwood at al (in preparation) suggested that 13 out of 27 interventions had no explicit link between theory and treatment rationale and only five had a strong theoretical underpinning limited to generic CBT models. This review did not access all treatment manuals and therefore some of these theoretical links could have been implicit in the treatment manuals but certainly there seemed to be a paucity of theory influencing treatment. Finally, it is possible that there are different sub categories of voice hearing. Therefore an approach which purely focuses on inner speech may not be providing the right type of intervention for other kinds of voice hearing experience. Garwood et al (in submission) has suggested that there were indeed subcategories and one subtype –hypervigilance hallucinations – were a small but consistent pattern of people’s presentations.
(iii) CBT for AVH: A New Treatment Manual
The rest of the presentation focussed on a treatment manual which has been developed as an attempt to address the issues raised above. This has been developed as a digital manual, accessible on an iPad to ease use and to provide video clips to help illustrate different points of psycho education. This treatment manual focuses on two types of voice hearing: inner speech and hypervigilance. The first part of the manual focuses on the assessment to try and identify which subtype of voice hearing the person is presenting with. It appears common for people to have both subtypes and it may be that hypervigilance hallucinations are a trigger for the development of inner speech hallucinations. The treatment then focuses on key areas to be addressed, starting with psychoeducation about the link between voice hearing and life’s strains. This is used to develop a formulation which highlights both the specific psychological factors behind voice hearing but also how the individual’s story fits with these models and how this has facilitated the progression of voice hearing. In many cases this takes the form of a vicious circle; noting this helps people understand how their experiences have escalated to such an extreme. Tailored coping strategies are then developed which also have the advantage of acting as behavioural experiments. For example, different techniques to block the phonological loop can give control over the experience but also help demonstrate that it is related to inner speech.
In later questions an example was given of how therapy would often proceed. The first session or two would be about developing a history, but in particular formatting this history to try and identify the types of factors which lead to voice hearing. These may include the nature of intrusive thoughts, factors which led to emotional and psychological strain, experiences which the individual may count as unacceptable and why this may be the case. By the end of session three they should be pulled together into a formulation which helps describe the development of voice hearing. This formulation is then used to guide the use of coping strategies which both confirm the formulation and give control and relief of symptoms to the individual. These coping strategies are often reviewed in sessions four and five but also other factors which may been important in the development of voice hearing may also be addressed at this point, for example issues concerning suppressing anger, bereavement or low self esteem.
Preliminary research into the treatment manual used a single case design. Twelve participants were identified, eight of which agreed to participate and seven of whom completed treatment. Their summary scores were shown where some people had strong effects from the treatment according to PSYRAT scores. However, the key to single case designs is people filling in diary measures so that there are repeated measures showing somebody’s day to day changes in symptomatology. The only two people who had completed the daily measures were poor responders according to the PSYRATs. However, one of these individuals, Elizabeth, actually had (according to single case design methodology) quite large effects which were attributable to the therapy. She had also experienced unwelcome effects from the treatment and difficult and abusive past experiences had been uncovered. The second person who had completed the diaries, Anya, showed very few changes, particularly in her understanding the attribution of the voice hearing. However, she did disclose some changes in control over her symptoms. Overall, the results suggested that the treatment shows promise and the next stage is to develop into a research for patient benefit bid to try and move towards an RCT study, comparing this to other forms of CBT for voice hearing.
(iii) Further Issues
At the end of the presentation several issues were raised. Some of the issues (why the evidence base is so weak, the more detailed description of what happened during the course of therapy) are addressed above. Other issues raised included:
(i) What is the relationship of mindfulness to this treatment? Mindfulness should provide an effective way of helping people detach themselves from the thoughts that they are experiencing if their voice hearing is related to inner speech. This potentially could be quite a powerful way of detaching from emotion and challenging the habit forming nature of thoughts. However, concerns were raised about creating a state where people are more likely to experience intrusive thoughts which could lead to a temporary escalation of difficulty and troublesome thoughts or voices. The importance of understanding why an intervention is being used and linking it to a formulation was highlighted.
(ii) Would this type of intervention fit with other forms of therapy for AVH? There are multiple approaches to treatment including medication, formulation driven treatments, coping strategy enhancement, compassion focussed therapy, Mindfulness and the hearing voices network approaches. These interventions often focus on different levels of explanation and intervention. For example medication reduces arousal. The intervention discussed focuses on formulation of coping strategies. Compassion focus therapy would maybe look at underlying factors such as low self esteem, shame or anger that may have influenced voice hearing experiences.
The last part of the discussion was taken up with focussing on how the hearing voices movement may either contradict or compliment this approach. Concern was raised that this presentation was describing an intervention which might further polarise this field with helping people create an alternative explanation for their experience and learning to control and manage their distress. Normalising how people are prone to get into such extreme states of life events is difficult. The hearing voices movement tries to help people take a positive stance toward their voice and see it as a life affirming experience. Therefore, one approach is aiming at new ways of understanding voice hearing and eradication of the voice hearing as the ultimate goal, another approach is helping people live comfortably with the experience. These could be seen as polarised approaches. The key is actually what the individual is seeking to achieve when they see a clinician. If somebody finds the experience distressing and wants it to stop then the approach will help them understand what they are experiencing and learn to control itIf somebody else has a long term relationship with their voice and is seeking to find a way to live more comfortably with them, but does not wish the experience to stop, then the hearing voices approach appears to be more valuable. It is unfortunate that approaches can appear to be polarised. The key for voice hearers is to be able to learn to manage and live well with the experience. One of the big gains of the last twenty or thirty years has been to see people with psychosis as having a psychosocial explanation for their experience which is meaningful and understandable. These approaches have all contributed to this change and if they are divided it might well slow this progress.