Exposure Therapy Study In Adults With Eating Disorders

The current proposal will evaluate the feasibility, acceptability, and preliminary efficacy of Exposure Therapy for anorexia nervosa (AN) spectrum disorders (Exp-AN), an innovative treatment rooted in principles of inhibitory learning. Exp-AN will target anxiety about both eating and weight gain by combining in vivo (i.e., in real life) and imaginal (i.e., mental) exposure in novel ways (e.g., eating a feared food while listening to a recording describing fears about weight gain).

The current proposal will evaluate the feasibility, acceptability, and preliminary efficacy of Exposure Therapy for anorexia nervosa (AN) Spectrum Disorders (Exp-AN), an innovative treatment rooted in principles of inhibitory learning. Exp-AN will target anxiety about both eating and weight gain by combining in vivo (i.e., in real life) and imaginal (i.e., mental) exposure in novel ways (e.g., eating a feared food while listening to a recording describing fears about weight gain).

The central hypothesis is that Exp-AN will effectively target anxiety related to eating and weight gain via inhibitory learning, and improve treatment outcomes. The investigator will test two aims:

Aim 1. Evaluate the feasibility, acceptability, and preliminary efficacy of Exp-AN.

Hypothesis 1.1: Exp-AN will be feasible, with satisfactory levels of recruitment (≥50%) and retention (≥75%).

Hypothesis 1.2: Participants will engage in Exp-AN, as measured by completion of the five treatment modules (≥80%) and therapy homework (≥60%).

Hypothesis 1.3: Participants will rate all five Exp-AN modules as acceptable.

Hypothesis 1.4: Exp-AN will result in increases in BMI and decreases in AN symptomatology.

Aim 2. Investigate Exp-AN's mechanisms of action, and if mechanisms are associated with positive outcomes.

Hypothesis 2.1: Exp-AN will result in decreases in anxiety between sessions, decreases in anxious beliefs, and increases in anxiety tolerance.

Hypothesis 2.2: Changes in anxiety ratings, anxious beliefs, and tolerance of anxiety will be associated with weight gain and reduced AN symptomatology.

Eligibility Criteria:
Inclusion Criteria:

1. Participants will be English speakers, ages 18 - 65 years, of all genders, with AN-spectrum disorders, defined as a diagnosis of AN, atypical AN, or AN in partial remission.

   1. Participants with AN, atypical AN, and AN in partial remission share the same DSM-5 criteria, with the exception of criterion A: "Significantly low body weight."
   2. Individuals with atypical AN are weight suppressed, but not "objectively" underweight (e.g., someone who experiences rapid weight loss from a BMI of 27 to 21). Those with AN in partial remission are partially or fully weight restored (e.g., after stepping down from an inpatient setting), but continue to experience significant AN behaviors (e.g., food avoidance) and/or cognitions (e.g., fear of weight gain).
   3. Diagnoses will be determined using the Structured Clinical Interview for DSM-5 - Research Version (SCID-5-RV).93 All participants in this study will be monitored by a Penn State Health medical provider.
2. All individuals who are deemed to be, or become, unsafe by their supervising medical provider will be admitted to our hospital or another facility for medical stabilization.

Exclusion Criteria:

1. Participants will be excluded if they are below 18 years of age.
2. Those identified as non-English speakers will be excluded due to lack of funding to translate the measures to other languages.
3. Individuals with other EDs (e.g., bulimia nervosa) will be excluded.
4. Participants will be excluded if they are:

   a.at high risk for suicide i.Suicide risk will be determined using the Columbia Suicide Severity Rating Scale (CSSRS) screen. The CSSRS will be administered by the study coordinator when they initially meet with the participant for Session 0 (see section 7 of this protocol), and at the start of every weekly session with the study therapist. The study coordinator and study therapists will be trained by the PI to adhere to a Suicide Assessment Protocol. This protocol will state that all participants who report high suicide risk should be sent by an ambulance to our institution's emergency department.

   b.pregnant determined by verbal verification (the study coordinator will ask participants if they are pregnant when completing the eligibility checklist and/or during the informed consent process).

   c. Meet DSM-5 criteria for a psychotic disorder and/or have an intellectual disability.