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The American Journal of GASTROENTEROLOGY VOLUME 107 | FEBRUARY 2012 www.amjgastro.com
ORIGINAL CONTRIBUTIONS nature publishing group
276
FUNCTIONAL GI DISORDERS
INTRODUCTION
Irritable bowel syndrome (IBS) is a functional bowel disorder
characterized by abdominal pain and / or discomfort, related to
abnormal bowel habits ( 1 ). Extra intestinal symptoms such as
nausea, lethargy, urinary symptoms, and backache are also com-
mon ( 2 ), and the same holds true for psychological co-morbid-
ity ( 3 ). is disorder is estimated to a ect 15 – 20 % of the general
population ( 4,5 ), and although only a small proportion see gas-
troenterologists, they account for approximately half of the vis-
its in gastrointestinal (GI) outpatients clinics ( 6,7 ). It is also one
of the most common GI diagnoses seen by general practitioners
( 8 ). However, a large proportion of subjects with IBS do not seek
healthcare for their bowel problems, or visit doctors infrequently,
whereas others consult frequently ( 9 – 11 ). e condition is more
common among women and the female / male ratio has been
reported to be as high as 4:1, but 2:1 is probably more accurate in
the general population ( 12 ).
e pharmacological treatment options for IBS patients are
based on treating individual symptoms such as diarrhea, pain,
constipation, and bloating, but unfortunately none of the available
pharmacological treatment option is e ective for all the di erent
IBS symptoms ( 13 ). Some of the patients have severe, intrusive
symptoms refractory to current conventional treatment options,
leading to substantial reduction in quality of life (QOL) and on
Effects of Gut-Directed Hypnotherapy on IBS in
Different Clinical Settings — Results From Two
Randomized, Controlled Trials
Perjohan Lindfors , MD
1 – 3 , Peter Unge , MD, PhD
4
,
5 , Patrik Arvidsson , PhD
2 , Henry Nyhlin , MD, PhD
6 , Einar Bj ö rnsson , MD, PhD
1 ,
Hasse Abrahamsson , MD, PhD
1 and Magnus Simr é n , MD, PhD
1
OBJECTIVES: Gut-directed hypnotherapy has been found to be effective in irritable bowel syndrome (IBS). How-
ever, randomized, controlled studies are rare and few have been performed outside highly specialized
research centers. The objective of this study was to study the effect of gut-directed hypnotherapy in
IBS in different clinical settings outside the traditional research units.
METHODS: The study population included IBS patients refractory to standard management. In study 1, patients
were randomized to receive gut-directed hypnotherapy (12 sessions, 1 h / week) in psychology private
practices or supportive therapy, whereas patients were randomized to receive gut-directed hypno-
therapy in a small county hospital or to serve as waiting list controls in study 2. Gastrointestinal
symptom severity and quality of life were evaluated at baseline, at 3 months follow-up and after
1 year.
RESULTS: We randomized 138 IBS patients refractory to standard management, 90 in study 1 and 48 in study 2.
In both the studies, IBS-related symptoms were improved at 3 months in the gut-directed hypnotherapy
groups ( P < 0.05), but not in the control groups (ns). In study 1, a signifi cantly greater improvement
of IBS-related symptom severity could be detected in the gut-directed hypnotherapy group than in
the control group ( P < 0.05), and a trend in the same direction was seen in study 2 ( P = 0.17). The
results seen at 3 months were sustained up to 1 year.
CONCLUSIONS: Gut-directed hypnotherapy is an effective treatment alternative for patients with refractory IBS, but
the effectiveness is lower when the therapy is given outside the highly specialized research centers.
Am J Gastroenterol 2012; 107:276–285; doi: 10.1038/ajg.2011.340; published online 4 October 2011
1 Department of Internal Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg , Gothenburg , Sweden ;
2 Department of Internal
Medicine, G ä vle County Hospital , G ä vle , Sweden ;
3 Department of Gastroenterology, Sabbatsbergs Hospital , Stockholm , Sweden ;
4 Ö rebro University
Hospital , Ö rebro , Sweden ;
5 Novartis Pharma AG , Basel , Switzerland ;
6 Department of Gastroenterology, Karolinska University Hospital , Stockholm , Sweden .
Correspondence: Magnus Simr é n, MD, PhD , Department of Internal Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg , 41345
Gothenburg , Sweden . E-mail: magnus.simren@medicine.gu.se
Received 23 February 2011; accepted 26 August 2011
© 2012 by the American College of Gastroenterology The American Journal of GASTROENTEROLOGY
277
FUNCTIONAL GI DISORDERS
Gut-Directed Hypnotherapy in IBS
psychological well-being ( 14 ). As a group, IBS patients seek health-
care more o en than other groups, for both GI and non-GI symp-
toms ( 15 ), and they have more time o work and o en undergo
repetitive expensive investigations. erefore, the costs to society
due to IBS are substantial ( 16 ) and e ective treatment options
leading to improved QOL and reduced time o work will have the
potential to be cost-e ective.
Several studies evaluating the e ects of psychological treat-
ments for IBS have been conducted, including cognitive behavior
therapy, gut-directed hypnotherapy, brief psychodynamic psycho-
therapy, relaxation therapy, and stress management ( 17 ). Although
these treatments generally show bene cial e ect, they have not
been widely disseminated in the clinical management of patients
with IBS. Gut-directed hypnotherapy, as a treatment option for
patients with severe IBS, was rst described in a randomized con-
trolled trial by Whorwell et al. in 1984 ( 18 ). In this study, up to
80 % of the patients reported improvement of their IBS symptoms.
e same group has therea er published several articles with
excellent long-term results regarding reduction of IBS symptoms,
improvement in QOL, reduction of extra intestinal symptoms,
and improved work productivity a er treatment with gut-directed
hypnotherapy in IBS ( 19 – 22 ). Small randomized, controlled stud-
ies from other groups have con rmed the results of the Manches-
ter group, although the results from these studies have not been
as impressive as in the original publication ( 23 – 25 ). Moreover, it
is not well established if it is possible to obtain good results, when
hypnotherapy is o ered outside highly specialized gastroenterol-
ogy research centers, even though promising results were reported
in one pilot study assessing gut-directed hypnotherapy in IBS in a
primary care setting ( 26 ).
erefore, in the present studies, we aimed to investigate, and
potentially con rm, the e cacy of gut-directed hypnotherapy as
a treatment option for patients with severe IBS, by performing
two randomized, controlled trials; one with patients recruited at a
center highly specialized in functional GI disorders, but with the
therapy performed in psychology private practices, and one at a
small- to medium-sized county hospital.
METHODS
Study design
Two separate randomized, controlled trials were conducted. Study 1
was performed at Sahlgrenska University Hospital, Gothenburg,
Sweden, where the patients were recruited in a highly specialized
unit for functional GI disorders, but the hypnotherapy sessions
took place in psychology private practices outside the hospital.
e second study (study 2) was conducted at G ä vle Hospital, a
medium-sized county hospital with a small gastroenterology
department with two gastroenterologists, serving ~ 100,000
inhabitants.
Patients with IBS refractory to standard management were
invited to participate in the studies. e participants should meet
the Rome II criteria for IBS ( 1 ). All patients underwent appropri-
ate GI diagnostic tests in order to rule out organic GI disorders
before inclusion, as judged by the treating physician. Patients with
other GI conditions explaining their symptoms, or with another
severe co-existing disease, were not included. e patients were
consecutively included among patients referred to the gastroentero-
logy departments at the two units for IBS symptoms refractory to
standard dietary and pharmacological therapies. Before randomi-
zation, all patients had a run-in period for at least 2 weeks where
the severity of symptoms was recorded (see below). In both studies,
patients were randomized to receive gut-directed hypnotherapy, or
to serve as a control subject. All subjects provided written informed
consent before inclusion and the studies were approved by the eth-
ics committee of the University of Gothenburg and the local ethics
committee at the County Council of G ä vle / Dalarna. If the patients
were on a stable dose of symptom modifying drugs for IBS, such as
antidiarrheals, bulking agents, or spasmolytics, they were allowed
to continue with their medication during the study, provided they
could continue on a stable dose of the medication during the study.
e use of psychotropic drugs or antidepressants was not allowed.
Gut-directed hypnotherapy
e intervention method used in these studies was based on the
gut-directed hypnotherapy described by the Manchester group
( 18 ). It was based on muscular and mental relaxation, and general
hypnotic suggestions were used either to focus on the symptoms
or to distract from them. A er feedback from the subject, indi-
vidual adapted suggestions were used to develop the ability of the
subject to bring forward a deeper feeling of being able to control
the symptoms. Speci cally, suggestions toward normalizing the GI
function were used, such as a river oating smoothly or a blocked
river cleared by the patient. e main strategy was to let the sub-
ject experience that they had an ability to control external stimuli
such as sounds, lights, and pressure from the surface of the chair,
and to gain control of inner physiological phenomenon such as
breathing and nally the IBS symptoms. All patients who partici-
pated in the studies were treated individually during 12 sessions,
each session lasting 60 min, once a week. e patients were told to
practice their hypnotic skills at home between the sessions on a
regular basis. Audiotapes were used in study 2 but not in study 1.
e psychologists had limited previous experience in gut-directed
hypnotherapy, but had received formal training from gut-directed
hypnotherapists, and had all conducted hypnotherapy for other
medical conditions for several years.
Study 1
We invited IBS patients according to the Rome II criteria ( 1 ) to
participate in the study performed at Sahlgrenska University Hos-
pital. ese were randomized by a study nurse in blocks of four
using numbered containers to receive gut-directed hypnotherapy
1 h per week for 12 weeks, or to serve as controls. e study nurse
was otherwise not involved in the analysis or interpretation of data
generated in the study, and the investigators (M.S., H.A., and E.B.)
were not at all involved in the randomization process, ensuring
treatment allocation concealment. ree experienced clinical psy-
chologists in private practices, specially trained in hypnotherapy
( > 10 years experience of general hypnotherapy), conducted the
treatment. e treatment was given outside the hospital at the
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FUNCTIONAL GI DISORDERS
Lindfors et al.
private practices of the psychologists. e patients randomized to
the control group were provided with supportive therapy to con-
trol for attention. ey met with a dietician once for 1 h to receive
general dietary advice with emphasis on good or bad food items
for IBS, and with a physiotherapist for 1 h, who provided general
information about relaxation training. Furthermore, a gastro-
enterologist with a special interest in functional GI disorders
(M.S., H.A., or E.B.) met the patients for 1 h and informed them
about GI physiology in general and the pathophysiology of IBS in
particular. Moreover, the study nurse telephoned the subjects in
the control group regularly during the treatment period for extra
support. e subjects in the control group were also informed that
they would receive gut-directed hypnotherapy a er 6 months,
which was recommended by the local ethics committee.
e e ectiveness of the treatment was evaluated with question-
naires (for detailed information see below) assessing QOL (IBS-
QOL), anxiety and depression (Hospital anxiety and depression
(HAD) scale), and GI symptoms (GI-symptom questionnaire). All
patients completed the questionnaires before the randomization
and directly a er the treatment, that is, at 3 months, and the pres-
ence of adverse events were assessed verbally by the psychologist
using an open question at the end of the sessions. e patients in
the hypnotherapy group were also evaluated concerning GI symp-
toms and QOL 1 year a er the gut-directed hypnotherapy treat-
ment using the GI-symptom questionnaire and IBS-QOL.
Study 2
We invited patients with IBS according to the Rome II criteria
( 1 ) to participate in the study at G ä vle Hospital. ese were ran-
domized by a statistician at the local research unit at the hospital,
otherwise not involved in the study, to receive gut-directed hypno-
therapy 1 h per week for 12 weeks or to serve as control group.
A randomization list using a computer program was used for this
purpose. e patients in the control group were informed that
they would receive gut-directed hypnotherapy a er 1 year, but
a er the randomization they did not receive any extra support,
but served as waiting list controls. Before the start of the study, all
patients received a thorough explanation about IBS in general by a
gastroenterologist (P.L.), who informed and reassured them about
the benign, but troublesome nature of the condition. ey were
given general advice about lifestyle changes to improve symp-
toms, factors known to trigger symptoms, and general informa-
tion about IBS. e hypnotherapy was given by one experienced
clinical psychologist, specially trained in hypnotherapy (P.A.)
(1 year experience). e treatment was given at the gastroenterol-
ogy outpatient clinic of the hospital.
e e ectiveness of the treatment was measured with validated
questionnaires (for detailed information see below) assessing QOL
(Short Form 36 (SF-36)), anxiety and depression (HAD scale), and
GI symptoms (Gastrointestinal Symptom Rating Scale IBS version
(GSRS-IBS)). All patients completed the questionnaires before the
randomization and directly a er the treatment period, that is, at 3
months, and the presence of adverse events were assessed verbally
by the psychologist using an open question at the end of the ses-
sions. e patients in the gut-directed hypnotherapy group were
also evaluated concerning the severity of GI symptoms 1 year a er
the treatment using the GSRS-IBS, and QOL using SF-36.
Primary outcome measures
GI-symptom questionnaires .
GI-symptom questionnaire used in study 1. is questionnaire
evaluates the perceived severity of symptoms related to IBS
during the past week, and was created speci cally for this
study ( 27 ). It uses a seven-graded Likert scale ranging from
no symptoms ( = 1) to very severe symptoms ( = 7). e higher
the score, the more severe are the symptoms. e symptoms
included are bloating, gas, pain, loose stools, urgency, hard
stools, and incomplete evacuation. e scores of the individ-
ual symptoms were then summarized into a total symptom
severity score ranging from 7 to 49 and two di erent domains:
sensory symptoms score (pain, bloating, and gas) and bowel
habit score (loose stools, urgency, hard stools, and incomplete
evacuation).
GSRS-IBS used in study 2. e GSRS-IBS is an IBS-speci c
questionnaire assessing the pattern and severity of IBS-related
GI symptoms during the past week using a seven-graded
Likert scale (1, no discomfort; 2, minor discomfort; 3, mild
discomfort; 4, moderate discomfort; 5, moderately severe dis-
comfort; 6, severe discomfort; and 7, very severe discomfort)
( 28 ). e GSRS-IBS consists of 13 questions, divided into ve
domains or syndromes: pain, bloating, constipation, diarrhea,
and satiety. e higher the score the more severe are the symp-
t o m s .
Secondary outcome measures
QOL questionnaires .
IBS-QOL used in study 1. is disease-speci c health-related
QOL instrument includes 30 items measuring nine dimen-
sions of health: emotional functioning, mental health, sleep,
energy, physical functioning, diet, social role, physical role,
and sexual relations ( 29 ). Raw scores are transformed into a
scale of 0 – 100, with 100 representing the best possible QOL
score.
SF-36 used in study 2. is is a widely used generic health-
related QOL measure with eight multi-item subscales (36
items), including physical functioning, bodily pain, general
health perceptions, vitality, social functioning, role limita-
tions due to emotional problems, and mental health ( 30 ). Raw
scores are transformed into a scale ranging from 0 (worst pos-
sible health state) to 100 (best possible health state) on each of
the eight subscales. A physical component score and a men-
tal component score can be calculated and used as summary
scores, and these were used in this study.
Questionnaire assessing anxiety and depression .
e HAD scale used in studies 1 and 2. is scale was devel-
oped for non-psychiatric medical patients to detect anxiety
•
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•
•
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© 2012 by the American College of Gastroenterology The American Journal of GASTROENTEROLOGY
279
FUNCTIONAL GI DISORDERS
Gut-Directed Hypnotherapy in IBS
97 Screened
90 Randomized
45 Active 45 Control
45 Completed the
3-month evaluation
7 Screen failures
3 Drop-outs
42 Completed the
3-month evaluation
45 Completed the
1-year follow-up
Figure 1 . Flowchart of study 1.
Table 1 . Baseline characteristics of the patients included in
study 1
Gut-directed
hypnotherapy
( n = 45)
Control
group
( n = 45)
Gender (female / male) 35 / 10 36 / 9 ns
Age (years) (mean (range)) 43 (26 – 68) 41 (21 – 67) ns
IBS subtype (A / C / D) 24 / 7 / 14 22 / 7 / 16 ns
IBS, irritable bowel syndrome.
A=alternating type IBS; C=constipation predominant IBS; D=diarrhoea predomi-
nant IBS.
and depression ( 31 ). It consists of 14 items, with 7 items relat-
ing to anxiety and 7 items related to depression. A four-graded
Likert scale is used (0 – 3), and the higher the score, the more
pronounced are the symptoms. e HAD scale is a reliable
instrument, with cuto scores, for screening for clinically sig-
ni cant anxiety and depression in patients attending a general
medical clinic and has also been shown to be a valid measure
of the severity of these disorders of mood.
Data analysis and statistics
Patient data and results from questionnaires were entered into
a database by persons otherwise not involved in the conduct of
the studies. All analyses were performed on an intention-to-treat
basis, including all patients who were randomized and completed
baseline questionnaires. For dropouts, we used the principle of last
observation carried forward technique and the data missing post-
treatment were imputed from baseline assessments and included
in the nal analyses. e analyses of the results from the ques-
tionnaires were made with parametric methods, that is, t -tests for
paired and independent samples, respectively. e change in GI-
symptom severity at 3 months relative to baseline (GI-symptom
questionnaire in study 1 and GSRS-IBS in study 2) was compared
between the hypnotherapy and control group in the two studies
separately, and constituted our primary end point (demonstrated
as mean di erence and 95 % con dence interval of the di erence).
We also performed within-group comparisons for these ques-
tionnaires, comparing results at 3 months with baseline for both
groups, and results from the 1-year follow-up evaluation relative
to baseline in the hypnotherapy groups. In an attempt to dem-
onstrate the response to the treatment more clearly, we de ned a
responder as a subject with reduction of the total symptom score
≥ 25 % on the GI-symptom questionnaire (study 1) or on GSRS-IBS
(study 2) at follow-up (3 months). e proportion of responders
in the hypnotherapy group vs. the control group was compared
using χ 2 test. Within- and between-group comparisons for the
QOL evaluations (IBS-QOL and SF-36), and anxiety and depres-
sion (HAD) were secondary outcome variables. No formal power
calculation was made to determine the number of patients to be
included, but these decisions were made based on the number of
patients in previous studies ( 32 ), and resources available at the
two sites, with the aim to end up with 90 evaluable patients in
study 1 and 45 patients in study 2. e scores from the question-
naires are displayed as mean ± s.d., unless otherwise stated. Statis-
tical signi cance was accepted at the 5 % level. No adjustments for
multiple comparisons were made.
RESULTS
Study population study 1
We invited a total of 97 IBS patients to participate in the study.
Seven of these withdrew their consent before randomization and
before completing any questionnaires, and were therefore not
included in the analyses. In all, 90 patients were randomized to
receive gut-directed hypnotherapy or belong to the control group
receiving supportive therapy. ere were no dropouts in the gut-
directed hypnotherapy group. In the control group, there were
three dropouts; one due to pregnancy and two due to withdrawal
of informed consent a er completing the questionnaires and
these patients were included in the analyses, based on the inten-
tion-to-treat principle ( Figure 1 ). No adverse events related to the
interventions were noted. e baseline characteristics of the rand-
omized subjects ( Table 1 ) were similar regarding gender, age, and
IBS subgroup according to the Rome II criteria ( 1 ) when compar-
ing the gut-directed hypnotherapy and the control group.
Study population study 2
We invited a total of 50 IBS patient to participate in the study. Two
of these withdrew their consent before randomization and before
completing any questionnaires, and were therefore not included
in the analyses. In all, 48 patients were randomized to receive
gut-directed hypnotherapy or belong to the control group. ere
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FUNCTIONAL GI DISORDERS
Lindfors et al.
the gut-directed hypnotherapy and control group regarding gen-
der, age, and IBS subgroup according to the Rome II criteria ( 1 ),
even though there appeared to be a slight numerical imbalance
between the groups regarding IBS subgroups.
Primary outcome measures
GI symptoms . Study 1. To evaluate the e ect of gut-directed hyp-
notherapy on GI symptoms, we used the GI-symptom question-
naire ( 27 ). e severity of GI symptoms was reduced in the gut-
directed hypnotherapy group at 3 months follow-up vs. baseline
( P < 0.01), and this was true for both sensory symptoms ( P < 0.01)
and bowel habits ( P < 0.05), whereas, no signi cant improvement
of GI symptoms was seen in the control group ( P = 0.7) ( Table 3 ).
When comparisons were made between the gut-directed hypno-
therapy and the control group, there was a signi cantly greater
improvement in total severity of GI symptoms in the gut-directed
hypnotherapy group (3.7 (0.3 – 7.2), (mean di erence (95 % con -
dence interval); P = 0.03), and this was also seen for sensory symp-
toms (2.2 (0.5 – 3.1); P = 0.01), but not signi cantly so for bowel
habits (1.6 ( − 0.6 – 3.7); P = 0.15), even though the trend was in
the direction of a greater reduction of the perceived severity of
bowel habit disturbance in the gut-directed hypnotherapy group
( Table 4 ). e symptom reduction in the gut-directed hypno-
therapy group was maintained 1 year a er treatment ( P < 0.01)
( Table 3 ). Using the responder de nition, that is, “ Reduction of the
total symptom score ≥ 25 % on the GI-symptom questionnaire, ” 17
patients were responders in the gut-directed hypnotherapy group
(38 % ) compared with ve in the control group (11 % ) ( P < 0.01).
At the 1-year follow-up, 19 patients met the responder de nition
in the gut-directed hypnotherapy group (42 % ). ere were no dif-
ferences in the results obtained by the three therapists (data not
shown).
Study 2. In study 2, we used the GSRS-IBS ( 28 ) to evaluate
GI-symptom severity. At the 3-month follow-up, there was a
were no dropouts in the control group. In the gut-directed hypno-
therapy group, there were three dropouts; one due to relocation
and two due to withdrawal of informed consent a er complet-
ing the questionnaires, and these patients were included in the
analysis based on the intention-to-treat principle ( Figure 2 ). No
adverse events related to the interventions were noted. e base-
line characteristics ( Table 2 ) did not di er signi cantly between
50 Screened
48 Randomized
25 Active 23 Control
22 completed the
3-month evaluation
2 Screen failures
3 drop-outs
23 completed the
3-month evaluation
22 completed the
1-year follow-up
Figure 2 . Flowchart of study 2.
Table 2 . Baseline characteristics of the patients included in
study 2
Gut-directed
hypnotherapy
( n = 25)
Control group
( n = 23)
Gender (female / male) 21 / 4 18 / 5 ns
Age (years) (mean (range)) 40 (22 – 60) 41 (21 – 58) ns
IBS subtype (A / C / D) 8 / 7 / 10 13 / 4 / 6 ns
IBS, irritable bowel syndrome.
A=alternating type IBS; C=constipation predominant IBS; D=diarrhoea predomi-
nant IBS.
Table 4 . Change in GI symptom severity at the 3-month follow-up
relative to baseline in study 1
Total GI
symptoms
Sensory
symptoms
Bowel
habits
Gut-directed hypnotherapy ( n = 45) 4.5 ± 8.6* 2.3 ± 4.2* 2.2 ± 5.6
Control ( n = 45) 0.8 ± 7.3 0.1 ± 3.9 0.6 ± 4.5
GI, gastrointestinal.
* P < 0.05 vs. control group.
Table 3 . Changes in GI symptom severity within the groups in study 1
Total GI symptoms Sensory symptoms Bowel habits
Baseline 3 Months 1 Year Baseline 3 Months 1 Year Baseline 3 Months 1 Year
Gut-directed hypnotherapy ( n = 45) 28.8 ± 6.8 24.2 ± 8.5*** 24.4 ± 8.7** 14.1 ± 3.6 11.8 ± 4.6*** 11.6 ± 4.7*** 14.6 ± 4.2 12.4 ± 5.1* 12.8 ± 5.0*
Control ( n = 45) 27.1 ± 6.9 26.4 ± 7.3 — 13.3 ± 3.5 13.2 ± 3.3 — 13.7 ± 4.3 13.1 ± 5.8 —
GI, gastrointestinal.
* P < 0.05, ** P < 0.01, *** P < 0.001 vs. baseline.
© 2012 by the American College of Gastroenterology The American Journal of GASTROENTEROLOGY
281
FUNCTIONAL GI DISORDERS
Gut-Directed Hypnotherapy in IBS
Table 5 . Changes in GI symptom severity, measured with GSRS-IBS within the groups in study 2
Gut-directed hypnotherapy ( n =25) Control ( n =23)
Baseline 3 Months 1 Year Baseline 3 Months
GSRS tot 4.0 ± 0.9 3.5 ± 1.0* 3.4 ± 1.1** 3.9 ± 0.9 3.9 ± 1.3
Pain 5.1 ± 1.2 4.3 ± 1.4** 3.9 ± 1.5** 4.8 ± 1.2 4.2 ± 1.7
Bloating 4.7 ± 1.5 3.9 ± 1.5*** 3.6 ± 1.4** 4.4 ± 1.5 4.5 ± 1.5
Constipation 2.9 ± 1.8 2.6 ± 1.6 2.3 ± 1.3 3.2 ± 0.9 3.0 ± 2.3
Diarrhoea 4.1 ± 1.4 3.6 ± 1.4 3.4 ± 1.3* 4.0
± 1.4 3.9 ± 1.5
Satiety 2.5 ± 1.6 2.9 ± 1.6 2.3 ± 1.2 3.0 ± 1.5 3.3 ± 1.6
GI, gastrointestinal; GSRS, Gastrointestinal Symptom Rating Scale; IBS, irritable bowel syndrome.
* P < 0.05, ** P < 0.01, *** P < 0.001 vs. baseline.
Table 6 . Change in GI symptom severity at the three-month follow up relative to baseline in study 2
GSRS tot Pain Bloating Constipation Diarrhea Satiety
Gut-directed hypnotherapy ( n =25) 0.43 ± 0.90 0.80 ± 1.24 0.75 ± 0.87** 0.30 ± 1.59 0.49 ± 1.36 − 0.38 ± 1.54
Control ( n =23) 0.10 ± 1.0 0.59 ± 1.48 − 0.07 ± 0.93 0.11 ± 1.66 0.14 ± 1.55 − 0.26 ± 1.30
GI, gastrointestinal; GSRS, Gastrointestinal Symptom Rating Scale.
* *P < 0.01 vs. controls.
signi cant reduction in the total GI-symptom severity ( P < 0.05)
in the gut-directed hypnotherapy group, whereas no signi cant
reduction was seen in the control group ( P = 0.7) ( Table 5 ). e
symptom reduction in the gut-directed hypnotherapy group was
more obvious and statistically signi cant for sensory symptoms,
such as pain and bloating, than for the perceived severity of diarrhea
and constipation ( Table 5 ). When we compared the change in the
severity of total GI symptoms between the gut-directed hypno-
therapy group and the control group, this did not reach statisti-
cal signi cance (0.33 ( − 0.22 – 0.91) (mean di (95 % con dence
interval); P = 0.22), even though the trend was in the direction
of numerically greater improvement in the gut-directed hypno-
therapy group. e same was true for the GSRS domains, with
no signi cant between-group comparisons, except for a greater
reduction of bloating in the gut-directed hypnotherapy group (0.82
(0.30 – 1.3); P = 0.003) ( Table 6 ). e reduction of GI-symptom
severity in the gut-directed hypnotherapy group was maintained 1
year a er treatment ( P < 0.01) ( Table 5 ). Using the responder de -
nition, that is, “ Reduction of the total symptom score ≥ 25 % on the
GI-symptom questionnaire, ” six patients were responders in the
gut-directed hypnotherapy group (24 % ) compared with three in
the control group (13 % ) ( P = 0.3). At the 1-year follow-up, seven
patients met the responder de nition in the gut-directed hypno-
therapy group (28 % ).
Secondary outcome measures
Quality of life . In study 1, we used IBS-QOL ( 29 ) to evaluate the
e ects on QOL. Measurements were made pre- vs. post-treat-
ment and in the treatment group a er 1 year. When comparing
measurements before and a er the treatment, a signi cant
improvement was seen in the gut-directed hypnotherapy group
in the dimensions of mental health ( P < 0.01), sleep ( P < 0.05),
energy ( P < 0.01), and social role ( P < 0.05) ( Table 7 ). Also, in the
control group, there was a signi cant improvement in the energy
dimension ( P < 0.01). e improvement in QOL was maintained
signi cantly for the same domains at the 1-year follow-up in the
gut-directed hypnotherapy group, but additionally there was also
a signi cant improvement in the dimension of emotional func-
tioning ( P < 0.01) vs. baseline. However, there were no signi cant
di erences in any of the dimensions in IBS-QOL when compar-
ing changes in QOL at the 3-month follow-up relative to baseline
between the gut-directed hypnotherapy group and the control
group ( P > 0.20).
In study 2, we used SF-36 ( 30 ) to evaluate QOL. When compar-
ing the measurements at baseline to post-treatment assessment,
a signi cant improvement ( P < 0.05) was seen in the gut-directed
hypnotherapy group in the physical component score, whereas no
change in the mental component score was observed ( Tab le 8 ). No
signi cant changes in the physical or mental component summary
scores were seen in the control group. ere were no signi cant dif-
ferences in any of the component scores when comparing between
the gut-directed hypnotherapy group and the control group. At the
1-year follow-up, there was still an improvement in the physical
component score in the gut-directed hypnotherapy group, but this
did not quite reach statistical signi cance ( P = 0.07).
Anxiety and depression . We used HAD in both studies at
the same time points, and therefore data from both studies were
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Lindfors et al.
different clinical settings, outside highly specialized hypno-
therapy units, in order to evaluate the potential to have this
therapy more widely spread compared to what is the case today.
In study 1, the patients were included at a gastroenterological
department at a university hospital, highly specialized in func-
tional GI diseases, but the therapy was given outside the hos-
pital in psychology private practices. Study 2 was performed in
a medium-sized county hospital with a small gastroenterologi-
cal department. Both studies aimed to evaluate gut-directed
hypnotherapy in IBS with improvement in GI symptoms as
the primary end point and improvement in QOL and impact
on psychological well-being as secondary end points. The two
studies are reported separately, but might be compared as the
studies are similar.
combined. e anxiety scores tended to be lower a er gut-directed
hypnotherapy ( P = 0.07), indicating less severe anxiety, whereas
no changes in the anxiety scores could be detected in the control
group, and the severity of depressive symptoms remained un-
changed in both groups ( Table 9 ). When between-grou p com-
parisons of the changes in HAD scores were performed, a greater
reduction for anxiety was seen in the gut-directed hypnotherapy
group than in the control group ( P < 0.05).
DISCUSSION
We here report the results from two randomized, controlled
trials evaluating gut-directed hypnotherapy as a treatment
option for severe IBS. The studies were performed in two
Table 8 . Changes in quality of life, measured with SF-36, within the groups in study 2
Gut-directed hypnotherapy ( n =25) Control ( n =23)
Baseline 3 Months 1 Year Baseline 3 Months
Physical component 38.1 ± 9.8 41.1 ± 10.4* 41.7 ± 9.3 39.3 ± 9.3 39.8 ± 11.0
Mental component 38.3 ± 12.1 36.5 ± 12.4 40.4 ± 16.2 31.8 ± 9.8 30.6 ± 14.0
SF-36, short form 36.
* P < 0.05 vs. baseline.
Table 9 . Changes in depression and anxiety (HAD) within the groups in study 1 and 2 combined
Gut-directed hypnotherapy ( n =70) Control ( n = 68)
Baseline 3 Months Baseline 3 Months
HAD anxiety 9.2 ± 4.3 8.6 ± 4.1 8.8 ± 3.4 8.9 ± 3.9
HAD depression 6.2 ± 3.2 6.2 ± 3.5 5.8 ± 3.4 6.0 ± 3.1
HAD, hospital anxiety and depression.
Table 7 . Changes in QOL, measured with IBS-QOL within the groups in study 1
Gut-directed hypnotherapy ( n = 45) Control ( n = 45)
Baseline 3 Months 1 Year Baseline 3 Months
Emotional functioning 43.6 ± 21.4 47.9 ± 22.3 53.7 ± 25.1** 45.1 ± 19.1 50.1 ± 19.6
Mental health 63.3 ± 20.1 73.4 ± 18.4** 71.3 ± 23.6* 68.3 ± 20.5 72.9 ± 16.2
Sleep 57.9 ± 24.9 64.0 ± 25.8* 66.9 ± 25.9* 66.0 ± 23.0 67.3 ± 24.5
Energy 38.9 ± 25.5 48.9 ± 25.1* 54.6 ± 28.4** 39.3 ± 25.1 48.5 ± 23.4**
Physical functioning 71.7 ± 25.6 74.0 ± 22.3 74.1 ± 26.4 74.2
± 25.6 76.5 ± 22.2
Diet 57.3 ± 17.4 54.6 ± 17.0 56.4 ± 17.8 55.9 ± 21.1 59.8 ± 15.9
Social role 49.4 ± 23.8 56.4 ± 23.2* 57.3 ± 26.4* 55.84 ± 25.6 59.2 ± 23.4
Physical role 42.7 ± 30.1 48.7 ± 33.5 49.7 ± 36.3 45.9 ± 28.2 50.0 ± 27.6
Sexual relations 49.7 ± 20.9 58.3 ± 25.0 61.3 ± 25.3 54.7 ± 25.7 55.2 ± 19.9
IBS, irritable bowel syndrome; QOL, quality of life.
* P < 0.05, ** P < 0.01 vs. baseline.
© 2012 by the American College of Gastroenterology The American Journal of GASTROENTEROLOGY
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Gut-Directed Hypnotherapy in IBS
e main nding of this study was a signi cant reduction in
IBS symptoms in both studies in the gut-directed hypnotherapy
groups. is was more pronounced for sensory symptoms, such
as pain and bloating, than for bowel habit disturbances. However,
in study 1, the severity of constipation and diarrhea was combined
in a composite bowel habit score, which might have prevented the
possibility to detect improvement in diarrhea and / or constipation,
but also in study 2, the positive e ect was more obvious for pain
and bloating than for bowel habits. No improvement in GI-symp-
tom severity was seen in the control groups. When comparison was
made between the treatment and control groups, the di erences in
IBS symptoms reached statistical signi cance in study 1, but not
in study 2, potentially due to smaller sample size in study 2. e
e ects on GI symptoms were sustained up to the 1-year follow-up
in both studies. We also noted a positive e ect on some of our sec-
ondary end points. Improvements in some of the QOL dimensions
were seen a er hypnotherapy, and anxiety tended to be lower a er
hypnotherapy, which is in line with previous ndings ( 33 ). How-
ever, the improvements seen in QOL did not di er signi cantly
between the active group and the controls at 3 months.
e results of our study do not reach the level of e ect reported
by the Manchester group ( 18,22 ) but are comparable to some other
controlled, randomized studies assessing the e ect of gut-directed
hypnotherapy as a treatment option for severe IBS patients ( 26,32 ).
Our results may re ect the fact that the psychologists in our stud-
ies are not highly specialized and experienced in gut-directed
hypnotherapy, which is the case in most other studies previously
presented. Also, the fact that we did not use audiotapes in study
1 may have in uenced our results, even though the subjects were
instructed to practice their skills at home regularly between the
sessions. Moreover, a more pronounced placebo e ect with the
hypnotherapy given at highly specialized centers, due to unspeci c
psychological e ects, such as higher treatment expectation, might
be expected. Our results re ect the e ectiveness of this interven-
tion when given outside the studies performed by highly special-
ized therapists with long experience in gut-directed hypnotherapy.
When asked a er the study, most of our patients responded that
they had a very positive experience of the hypnotherapy in terms
of general well-being and that they had found a way to cope with
their symptoms. is is in contrast with the fact that some of them
did not report so much improvement in GI-symptom severity,
when completing the symptom questionnaires. Measuring GI-
symptom severity with questionnaires as the primary end point
may not be the most accurate way to evaluate the results of psycho-
logical treatment options in functional GI diseases. Instead, evalu-
ation of, for instance, the general satisfaction with the treatment
alternative, and evaluate if the patient can handle their symptoms
better, might be a better way to assess the e ectiveness of di erent
non-pharmacological treatment alternatives. Unfortunately, such
assessments were not included in our study in a formal way, which
could have been useful.
e responder rate in patients receiving gut-directed hypno-
therapy was 11 – 27 % superior to the control groups. During the last
decade, a number of new drugs for IBS have been developed and
marketed. e e ectiveness is not dramatic and the general theme
has been that they are superior to placebo with about 10 – 15 %
( 34 – 36 ). Some of the newer drugs for IBS have also been associ-
ated with side e ects, which has led to withdrawal from the mar-
ket ( 37,38 ). When comparing the responder rate to gut-directed
hypnotherapy with the e ect of these new and o en expensive
drugs, hypnotherapy seems to be at least as e ective and without
any known side e ects. Moreover, the long-term e ect of gut-
directed hypnotherapy seems to be good in our study, as well as in
other studies ( 20 ), and the cost-e ectiveness is probably favorable
as well ( 21 ).
In study 2, no signi cant di erence between the groups regard-
ing our primary end point, that is, change in GI-symptom severity
at the 3-month follow-up relative to baseline, could be detected,
even though the trends were clearly in favor of the gut-directed
hypnotherapy. e reason for this is probably a type 2 error, due to
relatively small number of participants. QOL improved in several
domains of the IBS-QOL scale (study 1), although not signi cantly
compared with the controls, probably also secondary to the sample
size, which was clearly lower than in pharmacological studies in
IBS. Small di erences were also seen in QOL in study 2, but, again,
a relatively small number of participants, together with the fact
that SF-36 is rather insensitive to changes, may have in uenced the
results. Both groups in the studies were controlled until the end
of the treatment phase, that is, up to 3 months. Since gut-directed
hypnotherapy is available in clinical settings in Sweden, it was con-
sidered unethical to keep the controls from receiving gut-directed
hypnotherapy longer than 3 months, and therefore no 1-year results
were available in the control group, which has to be considered as a
drawback. When performing randomized controlled trials assess-
ing the e ectiveness of psychological interventions, it is di cult to
create a valid control group. In study 1, we attempted to control for
attention by o ering the subjects in the control group supportive
and educational treatment options, whereas in study 2, the control
group was just on the waiting list and no active control treatment
was given. is can be considered to be a weakness in study 2, but
we could not observe any obvious di
erence between the results in
the two control groups, where one was controlled for attention, the
other not. However, future studies should control for the regular
prolonged interaction with the health-care providers in order to
appropriately test the e cacy of gut-directed hypnotherapy in a
“ real world ” setting.
We have evaluated gut-directed hypnotherapy as a treatment
option for patients with severe IBS, given outside the highly spe-
cialized gastroenterology research centers, with a special interest
in gut-directed hypnotherapy. Although the reported e ects on
IBS symptoms are less positive compared with some of the previ-
ous studies within this area, it seems to be an important and use-
ful therapeutic option also in this treatment environment. e
responder rate for this type of treatment is at least as good as for
some of the new, expensive pharmacological treatment options.
e former, and the fact that there is no known side e ects makes
gut-directed hypnotherapy an interesting treatment option for
otherwise treatment refractory severe cases of IBS, and may also
prove to be cost-e ective in the long run. It now seems impor-
tant to further improve cost-e ectiveness, by nding predictors for
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a positive response in order to o er this treatment alternative to
those who are most likely to respond favorably.
ACKNOWLEDGMENTS
We express our gratitude to the three private practice psychologists,
who gave the hypnotherapy in study 1 — Susanna Carolusson, Berndt
Westman, and Anne Holmgren, and to Martha Sj ö berg, psychologist
at Ersta Hospital who trained P.A. in gut-directed hypnotherapy.
CONFLICT OF INTEREST
Guarantor of the article: Magnus Simr é n, MD, PhD.
Speci c author contributions: Paper writing, study design, PI
study 2, and data analysis: Perjohan Lindfors; study design study 2
and paper review: Peter Unge and Henry Nyhlin; hypnotherapist
study 2, study design study 2, and paper review: Patrik Arvidsson;
study design and performance of study 1 and paper review: Einar
Bj ö rnsson and Hasse Abrahamsson; PI study 1, study design, data
analysis, and paper writing: Magnus Simr é n.
Financial support: is study was supported by V ä stra G ö taland
Region (Dagmar funds); the Swedish Research Council (Grant
13409), the Faculty of Medicine, University of Gothenburg; and the
Centre for Clinical Research, G ä vleborg.
Potential competing interests: None.
Study Highlights
WHAT IS CURRENT KNOWLEDGE
3 Gut-directed hypnotherapy is considered to be an effective
treatment alternative for patients with severe irritable bowel
syndrome (IBS).
3 Few randomized, controlled studies exist assessing the
effectiveness of gut-directed hypnotherapy in IBS and none
has been performed outside the traditional research units.
3 Gut-directed hypnotherapy is not widely used in patients
with IBS, partly due to problems with availability outside
specialized centers.
WHAT IS NEW HERE
3 Gut-directed hypnotherapy is an effective treatment alterna-
tive for patients with refractory irritable bowel syndrome
(IBS), but the effectiveness is lower when the therapy is
given outside the highly specialized research centers.
3 Still, the effectiveness of gut-directed hypnotherapy is
superior to the available pharmacological treatment options
for IBS, supporting the spread of hypnotherapy into
community settings.
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