Anorexia Nervosa
Conditions
Brief summary
The main aim of this study is to develop a virtual reality (VR) embodiment-based exposure technique to improve the treatment of anorexia nervosa (AN). A systematic and hierarchical body exposure intervention in which the patient owns a virtual avatar is proposed. At first, the virtual body matches with the real measurements of the patient, then the experimenter will progressively increase Body Mass Index (BMI) values of the virtual body during the exposure sessions until a healthy BMI value is reached (e.g. BMI score of 20). In this study a VR embodiment-based technique that combines visuo-motor and a visuo-tactile stimulation procedures is proposed in order to increase illusory feelings of ownership over the virtual body. It is hypothesised that adding a VR-based body exposure intervention to the classical cognitive behavioral therapy (CBT) will significantly reduce symptomatology in AN patients.
Detailed description
In order to evaluate the efficacy of the addition of a VR body exposure component to the usual treatment, a randomized controlled clinical trial will be conducted. 54 patients with a primary diagnosis of anorexia nervosa and a BMI \> 18.5 will be randomly assigned to the experimental group receiving VR body exposure in addition to cognitive behavioral therapy or control group, which receives cognitive behavioral therapy only. Data regarding eating disorder symptomatology and body related attention will be collected before and at the end of the intervention, as well as after six months of follow-up. In the systematic and hierarchical VR body exposure intervention, which consists of 5 weekly exposure sessions, patients will gradually be exposed to increases in the BMI of their virtual avatar. Each session starts by inducing illusory feelings of ownership over the virtual body by the means of visuo-tactile and visuo-motor stimulation. Then patients are exposed to their virtual bodies in order to achieve the habituation or extinction of the anxiety response to their body image and, consequently, reduce the fear of gaining weight. During exposure, patients will be asked to focus on different parts of the virtual body, by asking what they think and feel about them. Body ownership illusion, body-related anxiety and fear of gaining weight will be assessed within each session by means of visual analogue scales.
Interventions
BEHAVIORALCognitive-behavioral therapy plus VR-based body exposure
Combine usual cognitive-behavioral treatment (CBT) sessions with additional five VR-based body-exposure therapy sessions.
BEHAVIORALCognitive behavioral therapy
Usual CBT
Sponsors
Hospital Sant Joan de Deu
Hospital Clinic of Barcelona
Hospital San Carlos, Madrid
Hospital Universitari de Bellvitge
Istituto Auxologico Italiano
University of Barcelona
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
14 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* patients with primary diagnosis of anorexia nervosa (DSM-V) * from the age of 14 years * with BMI \<18.5
Exclusion criteria
* visual deficits * epilepsy or neuroleptic medication * psychotic disorder * bipolar disorder * medical complications * pregnancy * clinical cardiac arrhythmia
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Change in Physical Appearance State Anxiety Scale (PASTAS) | from pre-assessment to post-assessment after 6 weeks | Evaluation of body-related anxiety using the PASTAS, with a maximum score of 32, with higher scores indicating higher body-related anxiety |
| Change in Silhouette Test for Adolescents (TSA) body distortion scores | from pre-assessment to post-assessment after 6 weeks | Evaluation of the change in body distortion in adolescents using the TSA body distortion scores, which can range from -3 to 3, with higher values indicating higher body distortion |
| Change in Silhouette Test for Adolescents (TSA) body dissatisfaction scores | from pre-assessment to post-assessment after 6 weeks | Evaluation of the change in body dissatisfaction in adolescents using the TSA body dissatisfaction scores, which can range from -3 to 3, with lower scores indicating higher body dissatisfaction |
| Figural Drawing Scale for Body Image Assessment (BIAS-BD) body distortion scores | from pre-assessment to post-assessment after 6 weeks | Evaluation of the change in body distortion in adults using the BIAS-BD body distortion scores, ranging from -80 to 80, with higher scores indicating higher body distortion |
| Figural Drawing Scale for Body Image Assessment (BIAS-BD) body dissatisfaction scores | from pre-assessment to post-assessment after 6 weeks | Evaluation of the change in body dissatisfaction in adults using the BIAS-BD body dissatisfaction scores, ranging from -80 to 80, with higher scores indicating higher body dissatisfaction |
| Change in Body Appreciation Scale (BAS) | from pre-assessment to post-assessment after 6 weeks | Evaluation of the change in body appreciation using the BAS, with a scale of possible scores ranging from 13-65, where higher scores indicate higher body appreciation |
| Change in Body Mass Index | from pre-assessment to post-assessment after 6 weeks | Evaluation of change in Body Mass Index |
| Change in Eating Disorders Inventory-3 (EDI-3) drive for thinness (EDI-DT) scale | from pre-assessment to post-assessment after 6 weeks | Evaluation of the change in drive for thinness, with maximum possible score of 28, where higher scores indicate higher drive for thinness |
| Change in Eating Disorders Inventory-3 (EDI-3) body dissatisfaction (EDI-BD) scale | from pre-assessment to post-assessment after 6 weeks | Evaluation of the change in body dissatisfaction, with maximum possible score of 40, where higher scores indicate higher body dissatisfaction |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Change in complete fixation time of the gaze towards weight-related body parts | from pre-assessment to post-assessment after 6 weeks | Evaluation of the attentional bias towards the body using complete fixation time (evaluated in milliseconds) of the gaze towards weight-related body parts, with higher values indicating a greater attentional bias |
| Change in number of fixations of the gaze towards weight-related body parts | from pre-assessment to post-assessment after 6 weeks | Evaluation of the attentional bias towards the body using the number of fixations of the gaze towards weight-related body parts, with higher values indicating a greater attentional bias |
Other
| Measure | Time frame | Description |
|---|---|---|
| Fear of gaining weight | Up to 40 minutes. Baseline (prior to beginning the body exposure session) and at the end of the body exposure session | Visual analogue scale from 0 to 100, with higher scores indicating higher fear of gaining weight |
| Body ownership illusion | Baseline (prior to beginning the body exposure session) | Visual analogue scale from 0 to 100, with higher scores indicating higher body ownership illusion |
| Body-related anxiety | Up to 40 minutes. Baseline (prior to beginning the body exposure session), every two minutes during the exposure, and at the end of the body exposure session | Visual analogue scale from 0 to 100, with higher scores indicating higher body-related anxiety |
Countries
Spain
Outcome results
None listed