BMJ...Mataix-Cols, Professor in child and adolescent psychiatric science 1 3, Linn Lichtenstein,...
Transcript of BMJ...Mataix-Cols, Professor in child and adolescent psychiatric science 1 3, Linn Lichtenstein,...
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Therapist-guided Internet-based cognitive behavioural
therapy for body dysmorphic disorder: A single-blind randomised controlled trial and cost-effectiveness study
Journal: BMJ
Manuscript ID: BMJ.2015.027352
Article Type: Research
BMJ Journal: BMJ
Date Submitted by the Author: 04-Jun-2015
Complete List of Authors: Enander, Jesper; Karolinska Institutet, Department of Clinical Neuroscience, Center for Psychiatry Research Andersson, Erik; Karolinska Institutet, Department of Clinical Neuroscience, Center for Psychiatry Research; Karolinska Institutet, Department of Clinical Neuroscience, Division of Psychology Mataix-Cols, David; Karolinska Institutet, Department of Clinical Neuroscience, Center for Psychiatry Research; Institute of Psychiatry, Psychology and Neuroscience. King’s College London, Department of Psychosis Studies Lichtenstein, Linn; Linköping University, Department of Behavioural Sciences and Learning Alström, Katarina; Linköping University, Department of Behavioural Sciences and Learning Andersson, Gerhard; Linköping University, Department of Behavioural Sciences and Learning Ljótsson, Brjánn; Karolinska Institutet, Department of Clinical Neuroscience, Division of Psychology Rück, Christian; Karolinska Institutet, Department of Clinical Neuroscience, Center for Psychiatry Research
Keywords: Body dysmorphic disorder, Obsessive-compulsive disorder, Cognitive behavioural therapy, Randomised controlled trial
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Internet-based CBT for BDD (BDD-NET) 1
Therapist-guided Internet-based cognitive behavioural therapy
for body dysmorphic disorder: A single-blind randomised
controlled trial and cost-effectiveness study
Jesper Enander, Clinical psychologist 1, Erik Andersson, Clinical psychologist 1 2, David
Mataix-Cols, Professor in child and adolescent psychiatric science 1 3, Linn Lichtenstein,
Assistant psychologist 4, Katarina Alström, Assistant psychologist 4, Gerhard Andersson,
Professor in clinical psychology 4, Brjánn Ljótsson, Senior lecturer 2 & Christian Rück, Senior
lecturer and consultant psychiatrist 1
1 Department of Clinical Neuroscience, Center for Psychiatry Research, Karolinska Institutet,
Stockholm, Sweden 2 Department of Clinical Neuroscience, Division of Psychology, Karolinska Institutet,
Stockholm, Sweden
3 Department of Psychosis Studies. Institute of Psychiatry, Psychology and Neuroscience.
King’s College London, UK 4 Department of Behavioural Sciences and Learning, Linköping University, Linköping,
Sweden
Corresponding author:
Jesper Enander
M46, Karolinska University Hospital Huddinge
SE-141 86 Stockholm, Sweden
E-mail: [email protected]
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Internet-based CBT for BDD (BDD-NET) 2
What is already known on this subject
The NICE guidelines recommend Cognitive Behavioural Therapy (CBT) for body
dysmorphic disorder (BDD) but most sufferers do not have access to this treatment.
The UK Government’s mental health strategy recommends the increased use of information
and communication technology to improve care and access to services. Internet-based CBT
(ICBT) is a burgeoning area of mental health aimed at increasing access to evidence-based
treatments for a range of mental disorders and other conditions.
A pilot study suggested that therapist-guided ICBT may be a highly acceptable, feasible and
potentially cost-effective treatment option for BDD. A randomised controlled trial is now
needed.
What this study adds
This is the largest clinical trial of BDD ever conducted, and the first RCT to evaluate the
efficacy and cost-effectiveness of therapist-guided ICBT for BDD (BDD-NET).
Our study suggests that BDD-NET is an efficacious and cost-effective way to dramatically
increase access to evidence based care for people with BDD.
BDD-NET may be particularly useful in a stepped-care approach, where mild to moderate
cases with low suicide risk can be offered BDD-NET by their general practitioner or other
health professional, thus freeing resources to treat more severe and complex cases in
specialised settings.
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ABSTRACT
Objectives: Cognitive behavioural therapy (CBT) is an effective treatment for body
dysmorphic disorder (BDD). However, most sufferers do not have access to such specialised
treatment. In line with NICE recommendations, there is an urgent need to increase access to
treatment for BDD sufferers. We aimed to evaluate the efficacy and cost-effectiveness of a
therapist-guided, Internet-based CBT programme for BDD (BDD-NET), compared to an
active control condition, online supportive therapy.
Design: A 12-week, single-blind, parallel-group randomised controlled trial.
Setting: Academic medical centre.
Participants: 94 adult outpatients with a diagnosis of BDD, and a Yale-Brown Obsessive
Compulsive Scale modified for BDD (BDD-YBOCS) score of ≥20. Concurrent psychotropic
medication was permitted if the dose had been stable for at least 2 months prior to enrolment
and remained unchanged during the trial.
Interventions: Participants received either BDD-NET (n=47) or supportive therapy (n=47)
delivered via the Internet.
Main outcome measure: The primary outcome was the masked assessor BDD-YBOCS score
at week 12, and at 3-month follow-up. Responder status was defined as a ≥30% symptom
reduction on the BDD-YBOCS.
Results: BDD-NET was superior to supportive therapy and was associated with significant
improvements of BDD symptom severity, depression, and quality of life. At follow-up, the
proportion of responders was 56% (95% CI 40% to 71%) amongst those receiving BDD-
NET, compared to 13% (95% CI 6% to 27%) in the supportive therapy group. The number
needed to treat was 2.34 (95% CI 1.71 to 4.35). BDD-NET had a 95% probability of being
cost-effective given a willingness to pay of £6000 for one additional remission and the
corresponding cost for one additional quality adjusted life year was £11000. Self-reported
satisfaction was high.
Conclusions: CBT can be delivered safely and cost-effectively via the Internet to patients
with BDD, thus dramatically increasing access to care for this severely under-detected and
under-treated mental disorder.
Trial registration: ClinicalTrials.gov ID: NCT02010619.
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INTRODUCTION
Body dysmorphic disorder (BDD) is a psychiatric disorder characterized by a pervasive
preoccupation with perceived defects in physical appearance accompanied by avoidance and
time-consuming compulsive behaviours, such as mirror gazing and excessive camouflaging to
hide perceived defects.[1] If left untreated, BDD is a chronic and unremitting disorder that is
associated with functional impairment across multiple life domains, relatively high rates of
psychiatric hospitalization, substance dependence, and suicidality.[2-4] Although the disorder
is frequently under-detected and underdiagnosed within the mental health services,[5,6]
epidemiological studies show that BDD is a common mental health problem with a
prevalence ranging from 0.7 to 2.2% in the general population. [7-10] It is common for
sufferers of BDD to seek non-psychiatric care, such as dermatological treatment or plastic
surgery, in an attempt to ‘fix’ the perceived defects; however, such interventions rarely work,
and can lead to a deterioration of the BDD symptoms.[11,12]
Evidence-based treatments for BDD include psychopharmacological treatment
and cognitive behaviour therapy (CBT).[13-16] Guidance from the National Institute for
Health and Clinical Excellence (NICE) recommends that adults with BDD should be offered
the choice of either a course of a selective serotonin response inhibitor (SSRI) or specialised
CBT that addresses the key features of BDD.[17] There is, however, a gap between supply
and demand of CBT due to various factors, such as a lack of trained therapists, direct and
indirect costs associated with treatment, and geographical barriers that prevent BDD sufferers
from receiving specialised CBT.[18-20]. In two surveys, only 10%-17% of people with body
dysmorphic concerns reported that they had received an empirically supported psychotherapy
(i.e., CBT), and 19%-34% reported that they had received an SSRI.[19,20] Thus, one of
NICE’s key priorities for implementation, namely that each primary care trust, mental
healthcare trust and children's trust that provides mental health services should have access to
a specialist BDD multidisciplinary team offering age-appropriate care is currently far from
reality.[17] The growth in demand for mental healthcare exceeds available UK National
Health Service (NHS) resources, and this gap is likely to increase up to 2020.[21] Cost
pressures require that providers find innovative ways to deliver services. The UK
Government’s mental health strategy ‘No health without mental health’[22] recommends the
increased use of information and communication technology to improve care and access to
services. UK Government initiatives such as ‘Digital First’ aim to reduce unnecessary face-to-
face contact between patients and healthcare professionals.[21] Many BDD sufferers report
that one important reason for not being in treatment is related to feelings of shame and stigma
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associated with their appearance concerns, making tele-care options potentially suitable for
this patient group.[19,20]
Internet-based CBT (ICBT) is a burgeoning area of mental health aimed at
increasing access to specialized behavioural treatments. In some countries (e.g., Sweden,
Australia and the Netherlands) ICBT has been implemented as part of the regular health care
system, and is efficacious and cost-effective for a wide range of mental health disorders.
[23,24] With the primary aim to increase access to evidence based care for BDD, we recently
developed a therapist-guided ICBT program for BDD (BDD-NET). In a pilot study, BDD-
NET was found to be safe, highly acceptable to patients and potentially efficacious.[25]
Crucially, the treatment only required a fraction of the therapist time associated with regular
CBT.
Here, we aimed to evaluate the efficacy and cost-effectiveness of BDD-NET
compared to online supportive therapy in the management of adults with BDD. Supportive
therapy was chosen as a control as most patients with BDD report that they receive non-
specific talking therapy when they seek help for their BDD.[19] We hypothesized that BDD-
NET would be superior to online supportive therapy in reducing BDD symptoms, as well as
other psychiatric symptoms, and improve quality of life. We also predicted that BDD-NET
would be cost-effective.
METHOD
Trial design
This was a single-blind, parallel-group, superiority trial conducted at the Karolinska Institutet,
between November 2013 and January 2015. Participants were randomly assigned to 12 weeks
of BDD-NET (n=47) or online supportive therapy (n=47) in a 1:1 ratio without restriction.
Participants randomised to supportive therapy were offered BDD-NET after the 3-month
follow-up. No changes to methods were made after trial commencement. The regional ethical
review board in Stockholm approved the protocol (registration ID: 2013/1773-31/4). US
National Institutes of Health (ClinicalTrials.gov) registration ID: NCT02010619. The study is
reported in accordance to the CONSORT statement for nonpharmacological treatments.[26]
Participants
Eligible participants were individuals with access to the Internet, aged 18 or over, and with a
principal diagnosis of BDD according to the DSM-5,[1] with a score of at least 20 on the
Yale-Brown Obsessive-Compulsive Scale Modified for BDD (BDD-YBOCS).[27] Exclusion
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criteria were: a) psychotropic medication changes within two months prior to enrolment, b)
completed CBT for BDD within the last 12 months, c) current substance dependence, d)
bipolar disorder or psychosis, e) acute suicidal ideation, f) a severe personality disorder that
could jeopardize treatment participation (e.g., borderline personality disorder with self-harm),
and g) concurrent psychological treatment. Participants who were taking psychotropic
medication, and had been on a stable dose for at least two months prior to enrolment were
asked to keep their dose stable during the study period. After complete description of the
study to the subjects, written informed consent was obtained.
Recruitment and determination of eligibility
Participants were recruited from all over Sweden. Flyers were distributed to psychiatrists and
general practitioners throughout Sweden with information about the study. In addition, the
study was advertised in national newspapers. Interested applicants had to register on the
study’s secure website and complete an online screening consisting of Montgomery-Åsberg
Depression Rating Scale Self-report (MADRS-S),[28] Alcohol Use Disorders Identification
Test,[29] Drug User Disorders Identification Test,[30] Body Dysmorphic Disorder
Questionnaire (BDDQ),[31] and general background information. The BDDQ is a screening
instrument for BDD, and has shown excellent sensitivity and specificity.[31] Potentially
suitable participants underwent a structured diagnostic interview with a clinical psychologist
or with a trained student in the final semester of a 5-year clinical psychology programme. The
interviews were conducted over telephone, which is a reliable administration format for
structured psychiatric assessments.[32] To establish a diagnosis of BDD, the Structured
Clinical Interview for DSM-IV Axis I Disorders was used, with an added question about the
presence of repetitive behaviours to reflect the updates made to the diagnostic criteria of
BDD in DSM-5. The Mini-International Neuropsychiatric Interview was used to determine
the presence of other comorbid psychiatric disorders.[33] All assessors had received extensive
training in structured diagnostic interviews. To ensure reliability of diagnostic procedure and
eligibility criteria, a consultant psychiatrist reviewed each case and made the final decision on
enrolment.
Interventions
BDD-NET
BDD-NET is delivered via a tailored online platform using a dedicated hospital server with
encrypted traffic and an authentication login function in order to guarantee participant
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confidentiality. Treatment length was 12-weeks, and none of the participants had any face-to-
face contact with a therapist. The treatment protocol is based on a CBT model for BDD,
emphasizing the role of negatively reinforced avoidance, and safety behaviours (e.g., mirror
checking, and camouflaging perceived physical defects) as maintaining factors of BDD. The
treatment protocol has been validated in a previous trial, and the treatment effects are
comparable to those gained in traditional face-to-face CBT.[25] The main intervention in
BDD-NET is systematic exposure to fear eliciting situations or events combined with
response prevention (E/RP) until anxiety and urges to ritualise subside (e.g., leaving one’s
apartment and refraining from compulsive mirror-checking).
In total, BDD-NET consists of eight interactive modules delivered over 12
weeks, with the first five modules containing the core treatment components.[23] Each
module is devoted to a special theme and covers: 1) psychoeducation, 2) a cognitive-behaviour
conceptualization of BDD, 3) cognitive restructuring, 4) E/RP, 5) more on E/RP, 6) values-based
behavior change, 7) difficulties encountered during treatment, and 8) relapse prevention. In
order to progress to the next module participants have to complete homework assignments
(e.g., reading text material, answering a quiz a the end of each module, filling out worksheets,
or doing E/RP), and report to their therapist. The participants had contact with an identified
therapist throughout the entire treatment using a built-in e-mail system on the BDD-NET
webpage. Participants could log in and send e-mails at any time. All homework assignments
and questions from the participants were reviewed and answered within 36 hours, except on
weekends. The role of the therapist was mainly to guide and coach the participant throughout
the treatment, provide feedback on homework assignments, answer questions from the
participants, and consecutively grant access to the next treatment module. The participants
were notified by an automated text-message (SMS) when they had a new e-mail in the
treatment platform from their therapist.
The therapists guiding the participants through the treatment were four clinical
psychology students in their final year of training with no prior experience of BDD. The
duration of therapist contact, and sent e-mails was automatically recorded by the BDD-NET
platform. Median therapist time spent weekly per participant reading and answering e-mails
was 13.2 minutes. To ensure treatment integrity and adherence to protocol, a clinical
psychologist monitored the messages sent by the therapists throughout the entire treatment,
and provided supervision. A screen-shot of BDD-NET appears in Figure S1.
Online supportive therapy
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Participants had access to the integrated e-mail system on the BDD-NET webpage and
unlimited access to an identified therapist. The therapist sent an email at least once a week,
encouraging the participant to discuss distressing life events and to promote problem solving.
All e-mails from the participants were reviewed and answered within 36 hours and the
participants were notified by an SMS when they had a new e-mail in the treatment platform.
Treatment length was 12-weeks, and none of the participants had any face-to-face contact
with a therapist. Non-directive supportive therapy has shown to reduce symptoms associated
with obsessive-compulsive disorder when delivered via the Internet,[34] however, there are
no reports of its efficacy for BDD. The supportive therapy served as a control for caregiver
attention and the possible anxiety-alleviating effect of sharing one’s distress with a therapist.
The same therapists that guided the participants through BDD-NET delivered the supportive
therapy. Median therapist time spent per participant per week reading and answering e-mails
was 6.3 minutes. To ensure treatment integrity, a clinical psychologist monitored the
messages sent by the therapists throughout the entire treatment, and provided supervision.
Randomisation and masking
An external person not involved in the trial used a true random number service
(www.random.org) allocating participants in a 1:1 ratio using simple randomization. The
random sequence was generated after inclusion to make sure that assignment of intervention
was concealed from the researchers involved in the study. Immediately after randomisation,
the participants received information about which treatment they had been allocated to, and
how they could log in to the secure website. Assessors in the trial remained masked to
treatment allocation at baseline, post-treatment and at 3-month follow-up. Due to the nature of
the intervention, participants and therapists were not blinded to treatment.
Assessment points and outcomes
Assessments were conducted at baseline, post-treatment, and 3 months after treatment. After
the 3-month follow-up, participants in the supportive therapy group who still wanted
treatment were offered to crossover to BDD-NET and re-assessed after receiving 12-weeks of
BDD-NET. Participants also completed online-self report measures at these time points, a
method which has been shown to be as reliable and as valid as pen-and-paper
administration.[35,36]
The primary outcome was change in BDD symptom severity assessed with the
clinician administered BDD-YBOCS.[27] The BDD-YBOCS can be considered the gold
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standard for assessing BDD symptom severity, and has a total score of 0-48, with a higher
score indicating more severe BDD. To ensure quality of assessments, clinicians in this trial
practiced together on case examples with excellent inter-rater reliability (intra class
correlation =.95, 95% CI .89 to .98).
Secondary outcomes included responder status defined as an empirically derived
cut-off point of ≥30% reduction from baseline on the BDD-YBOCS.[37] Remission was
defined as no longer meeting diagnostic criteria for BDD. Clinician rated global functioning
and improvement was assessed with the Global Assessment of Functioning scale (GAF),[38]
and the Clinical global improvement scale (CGI-I).[39] Depressive symptoms were assessed
with the MADRS-S.[28] Quality of life was assessed with the EQ5D EuroQol (EQ5D).[40]
Health economic cost data were collected using the Trimbos and Institute of Medical
Technology Assessment Cost Questionnaire for Psychiatry (TIC-P)[41] and includes data on
monthly health care visits, medication consumption, unemployment, sick leave, and work-
and household cutback. The occurrences of adverse events were recorded mid-treatment and
post-treatment using a self-report form.[42]
Power calculation and statistical analysis
A sample size of 39 per group was required to give 80% power and a two-sided 5%
significance for detecting at least a beneficial mean difference of 4 and a standard deviation of
6.24 on the BDD-YBOCS between BDD-NET and supportive therapy. These assumptions
were made based on a previous pilot trial of BDD-NET.[25] There was an anticipated 10%
dropout rate, giving a planned sample size of at least 44 per group, or 88 in total. There were
no planned interim analysis or stopping rules.
Analyses were by intention to treat, with participants analysed in the group to
which they had been randomised. Missing data were deemed to be missing at random using
Little’s MCAR test. Linear mixed models (LMM) with maximum likelihood estimations were
used to evaluate the effect of treatment group on the different outcomes. LMMs take into
account the inter-individual differences in intra-individual change with repeated responses
and use all the available data on each participant.[43] The fixed part of the model included a
treatment indicator variable (supportive therapy=0; BDD-NET=1), a time indicator variable
(baseline=0; post-treatment=1; follow-up=2), and a treatment � time interaction with
participant varying intercepts included as a random effect in the model. As therapist support
time varied between the two treatment arms it was included as a covariate, however, because
it did not predict outcome (p=0.22-0.95) it was dropped from the final model. Categorical
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data were analysed using Chi-square tests, and independent t-tests were used for assessing
between-group differences when time was not a factor on the outcome variable. The dose-
response of BDD-NET was investigated by regressing the post-treatment BDD-YBOCS score
on the number of completed modules, while controlling for the baseline BDD-YBOCS score.
Between-group effect sizes were calculated using Cohen’s d.
Costs of medication and health care visits were estimated using national tariffs
in Sweden, and were extrapolated to a 6-month period in order to get an estimate covering the
entire trial period. That is, monthly costs were extrapolated to the next measurement point
from baseline to post-treatment to follow-up. Productivity losses were based on the human
capital approach, and the costs of reduced work productivity were estimated based on the
average gross earnings in Sweden for 2013. The domestic loss hourly tariff was estimated to
£7.[44] Costs were converted from Swedish kronor (SEK) to pound sterling (£) using
purchasing power parities for the reference year 2013.[45] The net benefit of each individual
was calculated according to the following formula: (λ x E) – ∆C where λ is the willingness to
pay, E is the efficacy (i.e., remission or gain on the EQ5D), and ∆C is the cost change from
baseline to follow-up. We calculated individual net benefits by assuming different values for
λ and a regression model with non-parametric bootstrapping (1000 replications) to estimate
the difference between BDD-NET and supportive therapy. Cost-effectiveness acceptability
curves were used to get a visual estimate of the total net benefit of BDD-NET. We used
remission as outcome variable and also gain on the EQ5D to estimate the cost of one quality-
adjusted life-year (QALY). The analysis used a societal perspective, including both direct and
indirect costs obtained from the TIC-P. All statistical analyses were done in STATA 13.1.
RESULTS
The flow of participants through the trial is depicted in Figure 1. At post-treatment, and at 3-
month follow-up there was a 1%, and 9% loss of data, respectively. Little’s MCAR test
suggested that the missing data met the assumption of missing at random (χ=42.57, df=52,
p=0.82). There were no significant differences in dropout rates across conditions at post-
treatment (χ=1.01, df=1, p=0.32), or at the 3-month follow-up (χ=1.11, df=1, p=0.29) and
dropouts did not significantly differ from completers on baseline demographics or on
symptom measures. Participants that first received supportive therapy were offered BDD-
NET at the 3-month follow-up; 6 declined and the remaining 41 crossed over to BDD-NET.
Sample characteristics at baseline are presented in Table 1.
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<INSERT FIGURE 1 ABOUT HERE>
<INSERT TABLE 1 ABOUT HERE>
Primary outcome
There was a significant group by time interaction effect on the BDD-YBOCS both from
baseline to post-treatment (β= -7.32, 95% CI -9.00 to -4.84, p=<0.001), and from baseline to
follow-up (β= -6.46, 95% CI -9.00 to -3.91, p=<0.001). Though the BDD-NET group
improved significantly more, the supportive therapy group also showed significant gains at
post-treatment (β= -1.87, 95% CI -3.62 to -0.13, p=0.036), and at follow-up (β= -3.23, 95%
CI -5.00 to -1.46, p=<0.001).
The mean reduction on the BDD-YBOCS score from baseline to follow-up was
-9.68 (95 % CI -11.51 to -7.85) in the BDD-NET group, and the corresponding number for
the supportive therapy group was -3.22 (95% CI -5.00 to -1.45). At follow-up, the mean
difference between the groups on the BDD-YBOCS score was -5.84 (95% CI -8.51 to -3.17),
in favour of BDD-NET, indicating a larger treatment effect of BDD-NET compared to
supportive therapy. The effects of treatment on masked assessor BDD-YBOCS by condition
over time are presented in Figure 2A.
<INSERT FIGURE 2 AROUND HERE>
Secondary outcomes
The proportion of participants classified as responders was significantly higher in the BDD-
NET group both at post-treatment, 54% (95% CI 40 to 69) vs 6% (95% CI 2 to 19; χ=25.42,
df=1, p<0.001), and at follow-up, 56% (95% CI 40 to 71) vs 13% (95% CI 6 to 27; χ=17.55,
df=1, p<0.001). The number needed to treat (NNT) was 2.34 (95% CI 1.71 to 4.35). The
corresponding number of participants in remission at post-treatment was 32% (95% CI 20 to
47) vs 2% (95% CI 0.2 to 15; χ=15.16, df=1, p<0.001), and 40% (95% CI 26 to 56) vs 9%
(95% CI 3 to 22%; χ=10.92, df=1, p=0.001) favouring the BDD-NET group. At 3-month
follow-up, 56% (95% CI 40 to 71) of the participants in the BDD-NET group were classified
as improved or much improved on the CGI-I, compared to 16% (95% CI 7 to 30) in the
supportive therapy group (χ=15.52, df=1, p<0.001).
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Depressive symptoms as measured with the MADRS-S decreased over the
course of the trial in the BDD-NET group, and there was a significant group by time
interaction effect from baseline to post-treatment (β= -4.53, 95% CI -7.60 to -1.46, p=0.004),
and from baseline to follow-up (β= -5.26, 95% CI -8.51 to -2.00, p=0.002). In the supportive
therapy group, there was no effect of time on the MADRS-S from baseline to post-treatment
(β= -0.53, 95% CI -2.69 to 1.63, p=0.630), or from baseline to follow-up (β= -0.77, 95% CI -
2.98 to 1.44, p=0.495).
On the GAF there was a significant group by time interaction effect; the BDD-
NET group improved from baseline to post-treatment (β= 7.07, 95% CI 4.97 to 9.17,
p=<0.001), and from baseline to follow-up (β= 7.17, 95% CI 5.02 to 9.34, p=<0.001). No
significant improvements were seen in the supportive therapy group at post-treatment (β=
0.58, 95% CI -0.90 to 2.05, p=0.446) or at follow-up (β= 0.71, 95% CI -0.79 to 2.22,
p=0.353).
Health related quality of life (EQ5D) did not improve for the BDD-NET group
at post-treatment (β= 0.86, 95% CI -0.21 to 0.19, p=0.114). However, at the follow-up the
group by time interaction effect was significant, showing an improvement in quality of life
(β= 0.16, 95% CI 0.05 to 0.27, p=0.005). In the supportive therapy group there was a non-
significant decrease of quality of life at both post-treatment (β= -0.07, 95% CI -0.15 to 0.00,
p=0.061), and at follow-up (β= -0.08, 95% CI -0.15 to 0.00, p=0.051). Predicted means of the
outcomes across the different assessment points, and treatment effects are presented in Table
2.
<INSERT TABLE 2 ABOUT HERE>
Intervention delivery and dose-response effects
Thirty-nine participants (83%) completed the core components of BDD-NET (modules 1-5)
and there was a dose response relationship between the number of completed modules and the
post-treatment BDD-YBOCS score (β= -1.05, 95% CI -2.05 to -0.06, p=0.039). This implies
that for every completed module the post-treatment BDD-YBOCS score would decrease by
1.05 points.
Treatment acceptability
Overall, BDD-NET was deemed highly acceptable by participants, as 29% were very pleased
with the treatment provided, 47% were pleased, 20% indifferent or somewhat displeased, and
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4% were very displeased. In total, 82% reported that if they were in need of additional CBT in
the future they would use BDD-NET, and 89% would recommend BDD-NET to a friend with
similar problems.
Cost effectiveness
BDD-NET had a 60% probability of being cost-effective given a societal willingness to pay
of £0 (Figure 3). If the willingness to pay for one additional remission rose to £6000, BDD-
NET had a 95% probability of being cost-effective. The corresponding price for one QALY
was £11000, with a 95% probability of being cost-effective. Detailed information about the
economic data at the different time points is presented in Table 3, and cost tariffs for health
care services used by the participants are presented in Table S1.
<INSERT TABLE 3 AROUND HERE>
<INSERT FIGURE 3 AROUND HERE>
Crossover patients
Participants in the supportive therapy group who crossed over to BDD-NET after the 3-month
follow-up (N=41) showed a significant decrease on the BDD-YBOCS after receiving BDD-
NET (β= -7.28, 95% CI -9.06 to -5.50, p<0.001; Figure 2B). In total, 43% (95% CI 27 to
60%) of the crossed over cases were classified as responders, and 29% (95% CI 16 to 46%)
were in remission at post-treatment.
Similar improvements were observed on the MADRS-S (β= -2.45, 95% CI -4.43
to -0.46, p=<0.016) and the GAF (β= 4.78, 95% CI 3.12 to 6.43, p=<0.001), but not on the
EQ5D (β= 0.07, 95% CI -0.02 to 0.16, p=0.131).
Adverse events and protocol deviations
No serious adverse events (AE) were reported (i.e., events leading to acute health risks
demanding admission to a hospital). However, 15 (32%) participants in the BDD-NET group
and 6 (13%) participants in the supportive therapy group reported mild AE (i.e., increased
levels of anxiety and general negative well-being) at the beginning of the trial, which had
subsided for everyone at post-treatment, except for four participants in the BDD-NET group
who still reported feelings of general negative well-being that they attributed to the treatment.
The occurrence of AE during treatment was not related to responder status at post-treatment
(χ=0.91, df=1, p=0.34).
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All participants on psychotropic medication at baseline reported that they had
kept their dose stable during the treatment period. After commencing the treatment, one
participant in the BDD-NET group had been prescribed an antidepressant, but was classified
as a non-responder at post-treatment. None of the other participants reported that they had
received any other type of health care during treatment. From post-treatment to follow-up,
three participants in the BDD-NET group, and two participants in the supportive therapy
group had received additional health care in the form of CBT, pharmacological treatment, or
both.
DISCUSSION
In this trial, the efficacy and cost-effectiveness of BDD-NET, a novel therapist-guided
Internet-based CBT programme for BDD was compared to online supportive therapy, a kind
of non-specific talking therapy that mimics the psychosocial support that most patients with
BDD report receiving in the real world.[19,20] Overall, BDD-NET was superior to supportive
therapy, and was associated with significant improvements of BDD symptom severity,
depression, global functioning, and quality of life. These gains were maintained up to 3
months after treatment. At the 3-month follow-up, the proportion of responders was 56%
amongst those receiving BDD-NET, and 39% no longer met diagnostic criteria for BDD, with
a NNT of 2.34. A majority of participants were satisfied with BDD-NET, despite no face-to-
face contact with a therapist and deemed the treatment as highly acceptable. Furthermore, the
cost-effectiveness analysis showed that BDD-NET produced both additional responders as
well as QALYs for a low cost, and at the £30 000 threshold (associated with NICE
recommendations), the probability of cost-effectiveness was practically 100%. The results
indicate that BDD-NET has great potential to greatly increase access to evidence-based
psychiatric treatment for patients with BDD, in line with the NICE priority recommendations
[17].
Strengths of this trial include the large sample size, the inclusion of a control
intervention, the use of masked assessors and minimal patient attrition. One potential
limitation of the trial is that the results may not be generalizable to the entire BDD population
as the participants were self-referred. However, most had been ill for many years, had had
previous contact with mental health services, and a fifth had undergone plastic surgery. We
took the precaution, on safety grounds, to exclude participants with substance dependence and
severe suicidal ideation, both of which are common among patients with BDD. Participants in
the supportive therapy group were less engaged in the treatment, compared to the participants
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receiving BDD-NET. This is reflected in the amount of time that the therapist spent reviewing
and answering e-mails. However, unspecific talking therapy is the most common type of
psychosocial intervention that BDD sufferers receive, making it ecologically valid as a
control. Furthermore, the estimated differences in treatment effects remained unchanged when
statistically controlling for amount of therapist contact. Another limitation is the use of a self-
reported questionnaire for assessing cost data. However, self-reported cost data have been
shown to be as reliable as hospital register data.[46]
Overall, our results are in line with previous studies of face-to-face CBT for
BDD,[14,15] but most participants in this trial had moderate symptom severity and reasonable
good insight. Thus, our sample might differ from the average BDD patient seen in specialist
clinical settings. Furthermore, although the proportion of comorbidities were the same in our
sample as in previous clinical trials, the average participant in our sample endorsed mild
depression, compared to moderate to severe depression as seen in the two recent RCTs of
CBT for BDD.[14,15] BDD-NET is not intended for the most risky and severe end of the
BDD spectrum.
The therapists providing online support had no prior experience of treating
BDD. BDD-NET is delivered online as a series of interactive modules, and the role of the
therapist is mainly to encourage the participant to engage in the treatment, making it
reasonable to assume that BDD-NET can be used in non-specialist settings. BDD-NET may
be particularly useful in a stepped-care approach, where mild to moderate cases can be
offered BDD-NET by their general practitioner, or other health professionals, thus freeing
resources for more severe and complex cases to be treated in specialized settings. Logistic
barriers are also eliminated, as patients receiving BDD-NET do not have to travel to the clinic
once a week to receive the treatment. This makes BDD-NET particularly promising in more
rural areas where the access to trained CBT therapists is limited.[18] Future stepped-care
trials of BDD-NET in non-specialist settings are warranted.
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FUNDING
Financial support was provided through the regional agreement on medical training and
clinical research (ALF) between the Stockholm County Council and Karolinska Institutet, the
Swedish Research Council (grant number: K2013-61X-22168-01-3), and the Swedish Society
of Medicine (Söderströmska Königska sjukhemmet, grant number: SLS3B4451) provided
funding for this study.
ACKNOWLEDGMENTS
The authors would like to thank Monica Hellberg, Sofia Eriksson, Vania Panes Lundmark,
Martin Runeborg, and Lina Anderhell for their invaluable help.
DATA SHARING
No additional data available.
COMPETING INTERESTS
All authors have completed the ICMJE uniform disclosure form at
www.icmje.org/coi_disclosure.pdf and declare: no support from any organisation for the
submitted work; no financial relationships with any organisations that might have an interest
in the submitted work in the previous three years; no other relationships or activities that
could appear to have influenced the submitted work.
CONTRIBUTORS
JE and CR had the original idea for the study and with DM-C, and BJ designed the trial
variables and obtained the funding. JE and CR were responsible for study supervision. JE,
CR, LL, KA, EA, BJ, GA and DM-C were responsible for the acquisition of the data. JE, EA
and CR carried out the statistical analysis. JE drafted the manuscript, which was revised by all
authors. All researchers were independent of the funders. The funders had no part in the study
design, in the collection, analysis, and interpretation of data, in the writing of the report or in
the decision to submit the article for publication.
TRANSPARENCY
The lead author JE (the manuscript’s guarantor) affirms that the manuscript is an honest,
accurate and transparent account of the study being reported; that no important aspects of the
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study have been omitted; and that and discrepancies from the study as planned (and if
relevant, registered) have been explained.
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Table 1: Socio-demographic and clinical characteristics of the sample. Variable BDD-NET
(N=47) Supportive therapy (N=47)
Gender Women 39 (83%) 41 (87%) Men 8 (17%) 6 (13%)
Age Mean age (SD) 33.87 (13.55) 31.32 (11.12) Min-max 18-72 19-66
Highest
education
Primary school 4 (9%) 6 (13%) High school 31 (66%) 23 (49%) College/university 11 (23%) 17 (36%) Doctorate 1 (2%) 1 (2%)
Occupational
status
Working 25 (53%) 28 (60%) Student 13 (28%) 10 (21%) Retired 2 (4%) 1 (2%) Unemployed 7 (15%) 6 (13%)
Disability pension 0 (0%) 2 (4%)
BDD-YBOCS Mean score (SD) 29.13 (5.02) 28.51 (4.56)
Min-max 20-40 20-42
Insight Good 19 (40%) 18 (38%)
Poor 22 (47%) 21 (45%)
Delusional 6 (13%) 8 (17%)
BDD duration Median length in years 16 16 Body areas of
concern
Mean number of body areas (SD) 8.17 (4.83) 7.4 (4.53)
Comorbidity
Current depressive episode 28 (60%) 23 (49%) Panic disorder 2 (4%) 0 (0%) Social anxiety disorder 15 (32%) 14 (30%) Generalized anxiety disorder 9 (19%) 9 (19%) Bulimia nervosa 2 (4%) 2 (4%) Attention deficit hyperactivity disorder
1 (2%) 1 (2%)
Obsessive-compulsive disorder 8 (17%) 3 (6%)
Current
medication SSRI 5 (11%) 8 (17%) SNRI 1 (2%) 1 (2%) Other antidepressants 4 (9%) 4 (9%) Mood stabilizers 3 (6%) 1 (2%)
Benzodiazepines 3 (6%) 0 (0%) Neuroleptics 2 (4%) 0 (0%) Methylphenidate 1 (2%) 1 (2%)
Plastic surgery Previous plastic surgery 13 (28%) 8 (17%) Mean no. of surgeries (SD) 2.61 (1.89) 1.88 (1.36) Min-max no. of surgeries 1-6 1-5
Abbreviations: BDD-NET, Internet-based Cognitive Behaviour Therapy for Body Dysmorphic Disorder; BDD-YBOCS, Yale-Brown Obsessive Compulsive Scale Modified for BDD, BDD, Body Dysmorphic Disorder; SSRI, Selective Serotonin Reuptake Inhibitors; SNRI, Serotonin–Norepinephrine Reuptake Inhibitors.
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Table 2: Predicted means and treatment effects (BDD-NET vs. supportive therapy) at baseline, post-treatment, and 3-month follow-up.
Outcome Predicted mean (SE) Treatment
effect 95% CI P
Effect size*
BDD-NET ST
BDD-YBOCS
Baseline 29.13 (0.94) 28.51 (0.94) – – – – Post-treatment 19.94 (0.94) 26.64 (0.94) –6.70 –9.31 to –4.10 <.001 0.95 Follow-up 19.45 (0.98) 25.29 (0.95) –5.84 –8.51 to –3.17 <.001 0.87 MADRS-S Baseline 18.92 (1.36) 18.83 (1.32) – – – – Post-treatment 13.85 (1.37) 18.30 (1.36) –4.45 –8.24 to –0.66 0.021 0.43 Follow-up 12.89 (1.46) 18.06 (1.38) –5.17 –9.11 to –1.23 0.010 0.58 GAF Baseline 55.32 (1.03) 57.32 (1.03) – – – – Post-treatment 62.97 (1.03) 57.89 (1.03) 5.07 2.22 to 7.93 <.001 0.68 Follow-up 63.20 (1.06) 58.03 (1.04) 5.17 2.27 to 8.07 <.001 0.71 EQ5D Baseline 0.71 (0.03) 0.75 (0.03) – – – – Post-treatment 0.73 (0.03) 0.67 (0.03) 0.05 –0.04 to 1.47 0.255 0.21 Follow-up 0.80 (0.04) 0.67 (0.03) 0.13 0.03 to 0.23 0.011 0.53 *Cohen’s d effect sizes calculated from observed data. BDD-NET, Internet-based cognitive behavioural therapy for body dysmorphic disorder; ST, supportive therapy; BDD-YBOCS, Yale-Brown obsessive compulsive scale modified for body dysmorphic disorder, MADRS-S; Montgomery-Åsberg depression rating scale – self report; GAF, Global assessment of functioning; EQ5D, EuroQol EQ5D. SE, standard error; CI, confidence interval.
Table 3: Mean societal costs in sterling pound (extrapolated to a 6-month period)
Baseline Post-treatment Follow-up BDD-NET (SD) Control (SD) BDD-NET (SD) Control (SD) BDD-NET (SD) Control (SD)
Direct medical 1168 (2445) 2007 (3889) 894 (1900) 885 (1610) 706 (1158) 538 (912)
Health care visits
1036 (2405) 1932 (3800) 773 (1760) 742 (1480) 633 (1037) 507 (896)
Medications 131 (357) 75 (113) 120 (325) 142 (735) 74 (231) 32 (60)
Direct non-
medical 129 (192) 102 (238) 75 (207) 49 (136) 82 (242) 90 (279)
Indirect non-
medical 1637 (3546) 1290 (2955) 920 (2001) 1282 (1705) 920 (2001) 1282 (1705)
Sick leave 740 (2418) 597 (2300) 274 (944) 467 (1245) 500 (2140) 285 (1185)
Work loss 631 (2212) 501 (1507) 385 (1175) 601 (1446) 339 (1173) 848 (1989)
Domestic 267 (700) 189 (529) 145 (309) 188 (342) 81 (177) 149 (285)
Total costs
(excl.
intervention
costs)
2935 (4844) 3397 (5525) 1775 (2831) 2192 (2705) 1710 (2831) 1911 (3329)
Therapist cost 325 (239) 158 (119) 325 (239) 158 (119)
Total costs
(incl. therapist
cost)
2935 (4844) 3397 (5525) 2100 (2865) 2350 (2758) 2090 (2891) 2076 (3347)
Abbreviations: BDD-NET, Internet-based Cognitive Behaviour Therapy for Body Dysmorphic Disorder; SD, Standard deviation.
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Figure 1: CONSORT flow diagram of study selection 168x211mm (300 x 300 DPI)
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Figure 2: Effect of treatment over time on the Yale-Brown Obsessive-Compulsive Scale modified for body dysmorphic disorder (BDD-YBOCS) with 95% confidence intervals.
Figure legend: Figure 2A depicts the predicted mean BDD-YBOCS scores at each time point with 95%
confidence intervals, broken down by treatment group. Figure 2B Depicts the predicted mean BDD-YBOCS scores with 95% confidence intervals of the participants that got crossed over to BDD-NET after the 3-
month follow-up. The 3-month follow-up was used as baseline (pre-treatment) and the participants were re-assessed after receiving 12 weeks of BDD-NET.
335x216mm (72 x 72 DPI)
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Figure 3: Cost-effectiveness acceptability curves: Quality-adjusted life years (QALY) and remission 173x86mm (300 x 300 DPI)
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Figure S1: Screen-shot of BDD-NET
173x106mm (300 x 300 DPI)
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Type of visit Unit Cost (£) a
General practitioner Consultation 123
Clinical psychologist Session 108
Medical specialist Consultation 270
Physiotherapist Contact 48
Nurse Consultation 63
Alternative care b Session 39
Self-help group Hour 7
a Costs are in pound sterling (£) for 2013.
b Costs for alternative care vary. If unknown, the mean price of £7 per session was
used.
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