Effects of Reduced Environmental Stimulation on Eating Disorders

Study Overview
=================
Brief Summary
-----------------
The study proposed in this protocol aims to document the physiological, subjective, behavioral, and neural effects of reduced environmental stimulation (floating) in patients with current or prior anorexia nervosa The primary aim of this study is to determine the safety of this intervention. Secondary aims including determining whether floating has an impact on symptom reports such as those related to anxiety and eating disorders.

Detailed Description
-----------------
Floating creates an environment with minimal visual, auditory, tactile, proprioceptive, and thermal input to the brain. The float rooms used in this study are both lightproof, and thus completely dark when the entry door is sealed and the lights are turned off, reducing all visual input to the brain. Each float room was constructed with thick soundproof walls, restricting most outside noises from entering the room, thereby reducing auditory input to the brain. A high concentration Epsom salt water solution allows individuals to effortlessly float on their back while remaining completely still, reducing both proprioceptive and tactile input to the brain. The temperature of the water is calibrated to the temperature of the skin ( 94° F) and the temperature of the air is calibrated to the temperature of the water, making it difficult to discern the boundary between air and water, thus reducing thermal input to the brain while minimizing the need for thermoregulation of the skin. While both float pools dramatically reduce external sensory information, it is important to note that participants are in full control over the experience. For example, participants can enter and exit the float pool whenever they choose. Each float pool also contains a blue LED light that can be turned on and off via an air-coupled light switch in the pool. Both float rooms contain a shower for cleaning before and after floating. In a prior study the investigators have found that healthy participants found the pool condition to be relaxing and stress relieving. The current study aims to determine the safety of floating with a clinical population, specifically individuals with a history of eating disorder who are of normal weight.

Official Title
-----------------
Examining the Effects of Reduced Environmental Stimulation on Eating Disorders

Conditions
-----------------
Anorexia Nervosa

Intervention / Treatment
-----------------
* Behavioral: Reduced environmental stimulation


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: Current or prior diagnosis of anorexia nervosa (AN) All AN participants must be weight-restored prior to their participation, defined as having a Body Mass Index (BMI) > 17.5 Exclusion Criteria: Any of the following DSM-V disorders: Schizophrenia Spectrum and Other Psychotic Disorders Bipolar and Related Disorders Currently being treated for their psychiatric condition as an inpatient. Active suicidal ideation with intent or plan (as determined by a psychiatrist or clinical psychologist for all participants who report an IDAS-II suicide score > 10). Morbid obesity (BMI > 40) or underweight (BMI < 17.5). Orthostatic hypotension (defined as a drop of ≥20 mm Hg in systolic blood pressure or a drop of ≥10 mm Hg in diastolic blood pressure when measured shortly after transitioning from lying down to standing). Certain drugs or medications consumed within the past week including any psychoactive drugs (e.g., MDMA, LSD, psilocybin, peyote, phencyclidine, ketamine), magnesium supplements (greater than 150mg) or milk of magnesia. Any antihistamine that causes drowsiness (e.g., Benadryl) or any alcohol consumed within the past 12 hours. Caffeine or nicotine consumed within the past 3 hours. For all other medications, participants must be stably medicated prior to participation (defined as having taken the medication for 6 weeks or longer). History of unstable liver or renal insufficiency; glaucoma; diabetes; significant and unstable cardiac, vascular, pulmonary, gastrointestinal, endocrine, neurologic, hematologic, rheumatologic, or metabolic disturbance. Pregnancy as detected by a urine test. Failure to adhere to Pre-float checklist. Non-correctable vision or hearing problems.

Ages Eligible for Study
-----------------
Minimum Age: 18 Years
Maximum Age: 80 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
No

Study Plan
=================
How is the study designed?
-----------------

Design Details

Primary Purpose: Other
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Float<br>One arm only: restricted environmental stimulation | Behavioral: Reduced environmental stimulation<br>* Participants will complete one arm involving four sequential float sessions. Float 1: chair float. Participants will first float in a comfortable chair in the supine position, for up to 90 minutes. The chair is in a room with sound and light attenuation. Orthostatic blood pressure (BP) will be measured before and after each float. Anxiety and body image will be measured afterwards. Float 2: open pool float. Participants will float for up to 90 minutes in an open pool (8 foot diameter, no enclosure). Orthostatic BP will be measured before and after each float. Anxiety and body image will be measured afterwards. Floats 3 & 4: domed pool float. Participants will float for up to 90 minutes in a domed pool the same size as the open pool, with an enclosure wall and 8 foot tall ceiling. Orthostatic BP will be measured before and after each float. Anxiety and body image will be measured afterwards. Each float will occur approximately 1 to 7 days apart.<br>* Other names: Floating;|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Orthostatic blood pressure | Defined as a drop of ≥20 mm Hg in systolic blood pressure or a drop of ≥10 mm Hg in diastolic blood pressure when measured shortly after transitioning from lying down to standing. | Immediately before and after each float session for 4 float sessions, spaced weekly to monthly for up to 16 weeks study duration | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Self-ratings of changes in emotional experience | Measured via self-report measure (Positive and Negative Affect Schedule X) | Immediately before and after each float session for 4 float sessions, spaced weekly to monthly for up to 16 weeks study duration | 
| Self-ratings of changes in physical experience | Interoceptive and exteroceptive sensations, measured via visual analogue scale (e.g., 0 to 100) | Immediately before and after each float session for 4 float sessions, spaced weekly to monthly for up to 16 weeks study duration | 
| Body image | Measured via Photographic Figure Rating Scale, Body Appreciation Scale, Body Image States Scale, Body Shape Questionnaire, visual analogue scale (e.g., 0 to 10). | Obtained at baseline and immediately after each float session for 4 float sessions, spaced weekly to monthly for up to 16 weeks study duration | 
| EEG changes during the float experience | May be measured during the first, second, and fourth float. | During the first, second, and fourth float for 4 float sessions, spaced weekly to monthly for up to 16 weeks study duration | 
| Heart rate variability during the float experience | Measured during the first, second, and fourth float. | Obtained at baseline and after the first, second, and fourth float for 4 float sessions, spaced weekly to monthly for up to 16 weeks study duration | 
| Eating disorder severity | Measured via the Eating Disorder Examination Questionnaire | Obtained during the first visit | 
| Trauma exposure | Measured via the Childhood Trauma Questionnaire | Obtained during the first visit | 
| Self-ratings of changes in anxiety | Measured via self-report measure (Spielberger State-Trait Anxiety Index) | Obtained at baseline and immediately before and after each float session for 4 float sessions, spaced weekly to monthly for up to 16 weeks study duration | 
| Self-ratings of anxiety sensitivity | Measured via the Anxiety Sensitivity Index | Obtained during the first visit | 

 Terms related to the study
=================
Keywords Provided by Centre Hospitalier Valida
-----------------
Reduced, Environmental, Stimulation