© Aile Trumm, BSc (Hons), C.Hyp
Adapted from master’s thesis in Health Research Methods, “Effectiveness of Hypnotherapy in Anxiety Disorders: a Systematic Review”, which was submitted to the University of Birmingham in September 2018. Thesis is available on request, free of charge.
A Brief History and Definition of Hypnotherapy
Since the times of ancient civilizations, hypnotherapy has been known and documented under different names, the ways of conducting the therapy have also differed. In 18th century Austria, hypnosis was known as “animal magnetism” or “mesmerism”, named after Franz Anton Mesmer. The word hypnosis comes from the Ancient Greek after “Hypnos” who was the God of sleep and was first coined in relation to treatment by the Scottish doctor James Braid (1795 – 1860) who is regarded by many as a first genuine hypnotherapist.
According to Clarke (2013), hypnotherapy is still not easily or consistently defined. National Health Service UK defines hypnotherapy as: “a type of complementary therapy that uses hypnosis, which is an altered state of consciousness”. American Psychological Association (2017) defines hypnotherapy as a “state of consciousness involving focused attention and reduced peripheral awareness characterised by an enhanced capacity for response to suggestion“. Giffiths (2017) argues that the latter definition is so vague that it could be applied to anyone watching advertisements on TV.
There are many different types of hypnotherapy. To name a few: traditional hypnotherapy, hypnoanalysis, Ericksonian hypnotherapy, cognitive-behavioural hypnotherapy, clinical hypnotherapy, solution focused hypnotherapy and Lesserian curative hypnotherapy. Neuro-Linguistic Programming, Past Life Regression, Time Line Therapy and many more are considered to be part of hypnotherapy according to Hypnotherapy Directory (2018).
The term “hypnosis” is used in research interchangeably for both hypnotic state and the procedure used to induce the state. Hypnosis usually involves suggestions for relaxation, calmness, tranquillity and imagery experiences, contrary to the stigma of mind control or mental submission. The hypnotic state may be distinguished from other states of consciousness, such as sleep, wakefulness, relaxation and meditation. Neuroimaging techniques have confirmed that distinction by demonstrating the role of divisions in the anterior cingulate and prefrontal cortices during the hypnotic state. There is evidence that hypnotic suggestions arouse changes in respective brain regions. Furthermore, recoding techniques such as biofeedback show that during the hypnotic state, the parasympathetic nervous system is activated. Therefore, the breathing slows down, the heart beats slower, the muscles in the body become relaxed and the rapid eye movements (REMS) are observed. Although the hypnotic state shares some similarities with sleep state (as hypnosis has been proven to be an alpha-wave state), it has been argued that it is not a sleep state, as the attention of the subject has been concentrated and he or she is aware of the sounds (therapists’ voice) and suggestions. Bass (1931) suggests that the hypnotic state only shares superficial resemblance to sleep, after discovering that the patellar reflex (the knee-jerk reaction) of patients in hypnosis was the same as if they were in the waking state, whereas during sleep there is no response. Therefore, major electroencephalographic (EEG) findings appear to support the altered state of consciousness view, validating participants’ subjective responses to hypnosis.
There is growing interest in providing hypnotherapy in healthcare settings, including the provision of hypnotherapy training to healthcare workers in the UK (Abudarham, 1991) as hypnotherapy may also be relatively quick and inexpensive, compared to more expensive and time consuming Cognitive Behavioural Therapy (CBT). In fact, Huston (2010) conducted a retrospective pre-post intervention looking into the effectiveness of hypnotherapy in treating generalised anxiety disorder (GAD), comparing hypnotherapy with CBT. No difference between these two treatments was found, therefore suggesting hypnotherapy was equally effective. Roy-Byrne (2015) mentioned that psychiatrists struggle to offer the instantaneous relief that is expected of them from anxious patients. On the other hand, the sensation of a hypnotic state may provide a feeling of relaxation rather quickly.
NICE’s (2011) decision to include hypnotherapy as a complimentary intervention for the treatment of anxiety disorders, based on one paper by Zhao et al. (2005). In the aforementioned paper, benzodiazepine treatment was compared to application of hypnotherapy and no significant difference was found, possibly suggesting an alternative to the medication (Zhao et al., 2005). There remains controversy over NICE’S decision. On the contrary, Nisith et al. (1999) argue in their trial that hypnotherapy may be considered as a possible alternative to medication when comparing hypnotherapy to alprazolam prescription. Hypnotherapy has no side effects, whereas there are known problems and side effects associated with most prescribed anxiety medications. Patients have reported feeling dazed and unfocused, even when prescribed low doses. People who are prescribed medication often experience medication hangovers as some of the tranquillisers are highly addictive. Taking commonly prescribed anxiety medication (benzodiazepines, beta blockers, SSRI antidepressants, Buspirone) may disrupt work, school and everyday functioning for the patient due to side effects, which may cause problems later due to withdrawal.
Anxiety disorders were recognised and distinguished from other mental health disorders causing a negative effect (for example depression), as early as Biblical times. They were even recognised by ancient Greek and Latin physicians and philosophers. Treatments comparable with modern day cognitive psychology were known to be utilised at the time. However, in the early years A.D. anxiety disorders were not recognised as separate disorders and only achieved differential classification status again in the late 19th century. Now, anxiety disorders are defined by The Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM–5) as: “disorders that share features of excessive fear, anxiety and related behavioural disturbances.” (p. 189). American Psychiatric Association (APA) defines anxiety disorders as: “differing from normal feelings of nervousness or anxiousness and involve excessive fear or anxiety”. Furthermore, there is an additional note about the diagnosis of anxiety disorders, which requires the fear or anxiety to be out of proportion to the situation or age inappropriate and hinders a person’s ability to function normally.
Classification of the types of anxiety disorder did not change significantly until 2013. DSM–V re-classified obsessive-compulsive (OCD) and post-traumatic stress disorders (PTSD) separately from anxiety disorders, whilst still maintaining emphasis on a close relationship between previous and current classification, placing them close in the manual and drawing links between them. At the same time, separation anxiety disorder and selective mutism were included as anxiety disorder subheadings. Therefore, anxiety disorders according to the new classification are as follows: separation anxiety disorder, selective mutism, specific phobia, social anxiety disorder (social phobia), panic disorder, panic attack specifier, agoraphobia, generalized anxiety disorder (GAD), substance/medication-induced anxiety disorder, anxiety disorder due to another medical condition, other specified anxiety disorder and unspecified anxiety disorder (DSM-V, 2013; p. 189). Although PTSD has been removed from DSM-V as aforementioned, it is still an anxiety disorder according to NHS and Anxiety UK.
Anxiety disorders represent one of the major groups of disorders seen in psychiatry and in medicine generally. In several countries, anxiety disorders are more prevalent than mood disorders (e.g. depression, bipolar disorder), substance use disorders and impulse control disorders. There are various estimates of current global prevalence of anxiety disorders ranging from 7.3% up to 33.7%. The National Institute for Health and Care Excellence (NICE) reports that in Europe 22% of patients in primary care present with some anxiety disorder per year, GAD being most prevalent. Women appear to be almost twice as likely to be affected than men, regardless of age and geographical location.
Research in Hypnotherapy
Hypnotherapy research for anxiety and depressive disorders has enjoyed considerable growth until the early 1990’s but has since seen a decline. Various possible explanations are offered for this trend. The change may be due to the loss of many influential prolific researchers who have retired. These senior academics, linked to their institutions, attracted funding and institutional support which many believe has not been equalled. Following the loss of leading research centres in hypnotherapy, research has become an individual pursuit.
There have been two eminent approaches to research in hypnotherapy. The first of these is hypnosis research, where the nature of hypnosis itself is researched. There have been significant research gains made regarding the nature of hypnosis, due to the development of cognitive neuroscience and the application of neuroimaging methods.
Hypnotherapy treatments have demonstrated efficacy for a number of conditions. There is indication from the existing systematic reviews that the strongest empirical support is for use of hypnosis treatments: in pain management, irritable bowel syndrome, insomnia, several stress-related medical conditions and PTSD symptoms. Limited and sometimes inconclusive evidence from literature reviews suggests that hypnotic treatments may also be effective for a wide variety of other problems and conditions such as depression and anxiety.
To further confuse matters, there are other perceived obstacles surrounding hypnotherapy research. Namely, that there are various misconceptions and fears surrounding hypnotherapy, most likely stemming from the historical background and misuse of hypnosis by those commonly referred as “showmen and charlatans”. Not all people who call themselves hypnotherapists are equally qualified in hypnotherapy training. There are issues surrounding practice regulations. For example, in the United Kingdom there are currently no laws to regulate the level of training and experience required to practice hypnotherapy. In the United States, most states exert little or no direct regulation over the practice of hypnotherapy. Therefore, it is necessary to include the hypnotherapy qualifications/experience of therapists in the research papers. Unfortunately, it is rarely done. In the light of the differences between therapies, it is necessary to point out which type of hypnotherapy has been utilised when researching the effectiveness in hypnotherapy. Unfortunately, also a rarely occurring practice in research.
An additional challenge may be that hypnotherapy research continues to be labelled “unscientific” in the broader research community (Polito, Barinier and Cox, 2016; Raz, 2011).
However, there is some indication that the misconceptions about hypnosis may be softening due to general research progress. For example, the National Institutes of Health in the United States of America has recognised hypnosis as a topic of interest and has begun to fund large-scale studies evaluating the efficacy and mechanisms of hypnosis treatments.
The objective of the dissertation was to systematically evaluate the relevant evidence for the effectiveness of hypnotherapy interventions used for treatment of anxiety disorders. Although the history of hypnotherapy is extensive and there are some good quality studies and systematic reviews* which investigate the effectiveness of hypnotherapy in pain relief, IBS and many other domains, it was unclear whether there will be enough good quality research regarding hypnotherapy and anxiety since the publication and recommendations by Coelho, Canter and Ernst were published (2007).
*Systematic review is a research method designed to sum up the best available research on a specific question. This is done by synthesizing the results of several studies.
There is only one previous systematic review known to the author about the efficacy of hypnotherapy in anxiety. A systematic review published in 2007 by Coelho, Canter and Ernst identified 14 Randomised Controlled Trials (RCT’s)* which explored the efficacy of hypnosis for the treatment of any type of anxiety. The overall quality of included research papers was low.
*RCT’s are considered a “gold standard” in research due to rigorous research methodology, part of it being the randomisation of participants to different research conditions and then measuring the effect of the treatment or intervention.
The systematic review by Coelho, Canter and Ernst (2007) investigated adjunctive therapy to hypnotherapy, without mentioning the type of hypnotherapy utilised. The author of the current review has identified a lack of systematic reviews investigating hypnotherapy as a standalone treatment when conducting scoping searches. As different types of hypnotherapy operate slightly differently, psychological treatments (such as CBT) in conjunction with hypnotherapy will be inappropriate with some types of hypnotherapy, such as Lesserian Curative Hypnotherapy which is a standalone treatment.
As it has been a decade since the last known systematic review and in light of claimed advances in hypnotherapy research, it was found to be beneficial to conduct an update as it might be beneficial to explore advances in anxiety treatment with hypnotherapy, especially including children, as anxiety disorders.
It was discovered that there were only three articles investigating the effectiveness of hypnotherapy in anxiety disorders despite a rather broad search strategy. Studies in this review were collated from a variety of settings. Participants were from psychiatric and general populations; the age range was from 6 to 66 years old. One study had only male participants and three had more females than males. The results of these studies all reported a significant difference in the measured outcomes favouring hypnotherapy compared to control groups. The results overall are inconclusive due to the methodological quality of the studies. Similar aspects of rigorous research were often not reported or conducted.
Although research in utilising hypnotherapy generally is promising, research regarding the use of hypnotherapy for treating anxiety disorders is insufficient to draw definitive inferences. Therefore, the current dissertation concluded that the evidence is insufficient to support the effectiveness of hypnotherapy in treating anxiety disorders and more research using more rigorous methodology is recommended as a result. The main issue appears to be the quality of RCT’s in hypnotherapy. Better quality research in the effectiveness of hypnotherapy appears still be one of the most pressing matters.
Implications for Clinical Practice and Future Research
Furthermore, the low volume of RCTs included in the review would indicate that in the past ten years, despite vast amount of case studies, there was few quantitative studies conducted regards anxiety treatment with hypnotherapy. A useful future research suggestion may be to also explore other research designs that outcome the effect of hypnotherapy for anxiety disorders and PTSD.
Clinical hypnotherapy appears to be the most popular due to its meshing with psychology. As clinicians are more likely to be trained in research methodology than hypnotherapists and conduct research and publish articles, there might be an additional bias towards the type of hypnotherapy that has been researched. To overcome these biases, it may be useful to utilise hypnotherapists from different types of hypnotherapy interventions to administer treatment as part of research design. Additional insight may include the effectiveness of different types of hypnotherapy in anxiety disorders. Furthermore, it may reduce the reporting bias and benefit research methodologically. It would appear that the experience or level of hypnotherapy training of person/people conducting hypnotherapy is rarely mentioned in the research papers and it appears to be acceptable that a qualified psychologist or psychiatrist may practice hypnotherapy without mentioning any formal training in hypnotherapy. It would be beneficial to integrate interdisciplinary collaboration in this research area, having well-designed studies, experienced researchers and experienced hypnotherapists working together. Alternatively, hypnotherapists may be trained in research methodology and conduct rigorous research in hypnotherapy or be aware of ongoing research and contribute with their knowledge and expertise in all stages of research design.
Despite concerns about effectiveness and regulation, hypnotherapy is becoming increasingly recognised as a potential method for reducing feelings of anxiety. In the past decade, there has been a vast increase in research interest regarding anxiety disorders due to the recognition of the prevalence, implications and morbidity burden of the illness. Hypnotherapy may have potential to provide a fast, cost-effective alternative to medication in the treatment of anxiety disorders, especially in children and young adults. It would be beneficial to scientifically research hypnotherapy in the treatment of children and young people as anxiety disorders usually have an early onset.
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