Clinical Case Study

Eating Disorder Treatment

Evidence-Based Integrated Approach — CBT-E + Mirror Exposure Therapy

This case demonstrates sustained recovery in a complex clinical presentation through an integrated CBT-E and Mirror Exposure Therapy approach, achieving full behavioral remission and significant functional restoration in a high-acuity adolescent patient.

Patient
18 y/o biracial cisgender female
Diagnosis
Bulimia Nervosa, Extreme Severity (F50.24)
Duration
13 months outpatient
Setting
Specialized Outpatient

Treatment Outcomes at a Glance

Key metrics demonstrating the impact of integrated CBT-E and Mirror Exposure Therapy across 13 months of treatment.

100%
Reduction in All Compensatory Behaviours
Self-induced purging, binge eating, laxative use, compulsive exercise
85%
Reduction in ED Cognitions
Eating disorder thoughts reported
42%
Improvement in EAT-40
Global score: 65 → 38
1 Year
Sustained at Follow-Up
Confirmed remission at 6-month & 1-year

The Clinical Challenge

Presenting Symptoms

Patient presented with increasing difficulties with eating and body image, with symptom onset in 6th grade coinciding with puberty.

  • Binge eating 5-6x/week with self-induced vomiting up to 15-18 episodes/day
  • Daily laxative use and compulsive exercise (up to 8 hours/day)
  • Co-occurring depression, anxiety, trauma, suicidal ideation, daily self-harm
  • Significant functional impairment: poor school attendance, college delayed, social isolation, family tension
Complicating Factors
  • History of Chiari Malformation with decompression surgery at age 10
  • AI chatbot misuse for reassurance-seeking, calorie tracking, diet advice, & body image distortion
  • Family discord — parents disagree on treatment; police involvement in conflicts
  • Nutritional deficiencies: fatigue, syncope, hair loss, amenorrhea. Medical complications including some parotid hypertrophy
  • Prior treatment resistant — multiple outpatient, residential, inpatient rounds

DSM-5 Severity Classification — Self-Induced Vomiting Frequency

Mild
Moderate
Severe
Extreme
1-3 episodes/wk4-7 episodes/wk8-13 episodes/wk14+ episodes/wk

Patient: 15-18 episodes/day — far exceeding the DSM-5 “Extreme” threshold of 14+ episodes per week. Combined with daily laxative abuse and up to 8 hrs/day compulsive exercise.

Treatment Journey — 13 Months

A phased approach moving from behavioural stabilization to cognitive restructuring to body image work.

Months 1-3 — Phase 1

Behavioural Containment & Stabilization

Established regular eating patterns, reduced medical risk from purging frequency, stabilized nutritional status. Collaborative formulation of maintaining factors.

CBT-E Phase 1
Months 4-7 — Phase 2

Cognitive Restructuring & Exposure

Targeted overvaluation of shape/weight, core low self-esteem, and mood intolerance. In vivo and interoceptive exposure to break rigid dietary rules.

CBT-E Phase 2-3
Months 8-11 — Phase 3

Consolidation & Relapse Prevention

Maintained behavioural gains, addressed interpersonal difficulties, built distress tolerance, improved emotional regulation. Prepared for transition to targeted body image work.

CBT-E Phase 4
Month 12-13 — Phase 4

Mirror Exposure Therapy (Technology-Integrated)

Prolonged guided body exposure, digital environment restructuring, graded social media re-engagement. Addressed AI chatbot misuse patterns.

MET + Digital Adaptations

Clinical Reasoning & Approach

Explore each component of the integrated treatment protocol.

Clinical Formulation

The patient is a 18 y/o female presenting with severe Bulimia Nervosa, marked by high-frequency and intensity binge-purge behaviours and complicated by comorbid major Depressive Disorder, anxiety, trauma-related symptoms, and daily non-suicidal self-injury (NSSI). Her presentation reflects multifactorial etiology with a pathology rooted in complex interplay of vulnerabilities, such as symptom onset emerging in the context of puberty and premorbid placement in upper weight percentiles. This developmental context triggered an initially ego-syntonic pursuit of health-conscious eating that rapidly intensified into an intense fear of weight gain, pronounced overvaluation of shape and weight, extreme rigidity in dietary restriction, and severe compensatory behaviours. These patterns suggest early development of maladaptive core beliefs related to self-worth alongside environmental triggers and genetic predisposition (mother has history of AN-R) reinforcing behavioural inflexibility, and emotion dysregulation.

Currently, the patient is in a severe restrict-binge-purge cycle driven both by psychological rigidity and physiological starvation. Severe caloric restriction (i.e: phobic avoidance of “contaminated” fats) trigger objective binge-eating episodes, which are subsequently neutralized through dangerous multi-modal compensatory behaviours including extreme self-induced vomiting (15-18x/day), daily laxative abuse, and compulsive over-exercise (up to 8 hours/day). This profound stage of malnourishment, neurobiological stress, and metabolic impairment actively sustains her pathology such as further destabilizing mood and amplifying intrusive suicidal ideation. Ultimately, the eating disorder and self-harm function together to modulate intense affect, which presents a complex clinical picture that requires an integrated intervention to rehabilitate nutritionally, disrupt the physiological behavioural cycle, and treat the underlying emotional dysregulation.

CBT-E (Enhanced Cognitive Behavioural Therapy)

Primary intervention as it is the leading evidence-based intervention for Bulimia Nervosa. CBT-E directly targets the core maintaining psychopathology—overvaluation of shape, weight, and their control. Its trandiagnostic approach is well suited for this patient’s clinical presentation, allowing for modular treatment of the maintaining mechanisms that cut across Patient’s comorbid presentations: core low self-esteem, interpersonal difficulties, poor emotional regulation, and marked mood intolerance. CBT-E’s 4 phase structure moving from establishing normalized eating to cognitive restructuring provides the containment this patient requires. Its emphasis on collaborative formulation fosters internal change essential for sustained recovery and long-term relapse prevention.

Mirror Exposure Therapy (MET)

Mirror Exposure Therapy, thereafter “MET”, was strategically sequenced to follow the stabilization of eating behaviour and nutritional rehabilitation through completion of CBT-E treatment. MET requires a degree of cognitive flexibility and distress tolerance that is neurobiologically compromised during active starvation. Once the behavioural cycle was disrupted and Patient achieved medical and nutritional stability, MET was introduced to target the significant body image disturbance that persisted despite behavioural gains—especially given Patient’s over-reliance on generative AI models and social media filters to reinforce negative body beliefs and avoidance behaviours. Through prolonged guided mirror exposure sessions, Patient systematically challenged the avoidance behaviours and attentional biases perpetuating distorted self-perception, gradually building tolerance for viewing her body without the distortions previously sustained by digital manipulation.

Treatment Adaptations

Early treatment prioritized behavioural containment—establishing regular eating, reducing medical risk from purging frequency, and stabilizing nutritional status—before any active cognitive or exposure work. Technology-integrated MET adaptations included having Patient take photos of self in session with neutral non-judgmental language, restructuring digital environment as response prevention by disabling image-editing and filter features, then graded exposure to posting unedited content—directly countering harmful AI chatbot and social media engagement patterns.

Measured Outcomes & Impact

Standardized assessments and behavioural data demonstrating clinical progress across 13 months.

Pre vs. Post Treatment Measures

Standardized assessment scores before and after 13-month treatment

Treatment Effectiveness Index

Composite effectiveness score across multiple outcome domains

Weekly Compensatory Behaviour Frequency

Tracking binge episodes, purge episodes, and excessive exercise hours over 52 weeks of treatment

Behavioural Frequency Reduction

Show pre-treatment Show post-treatment
15-18x/day
0
Self-Induced Vomiting
5-6x/week
0
Binge Episodes
Daily
0
Laxative Use
8 hrs/day
Healthy
Exercise

Functional Recovery Milestones

  • Weight Restoration
    144 lbs → 161 lbs (BMI 22.0 → 23.8)
  • Full-Time School Return
    From poor attendance to full-time engagement
  • Zero Returns to HLOC
    No higher-level-of-care admissions at 6-month & 1-year follow-up
  • Eating Pattern Normalized
    3 meals + 2-3 snacks daily; flexible food choices
  • Digital Health Restored
    AI chatbot dependency & harmful social media use resolved

Multi-Dimensional Improvement — Click dimensions to explore

Pre-treatment (outer, dashed) vs. Post-treatment (inner, filled) — lower is better

Scalable Insights for Digital Health

Clinical protocols and measurement approaches that could be systematized for scalable delivery in digital health platforms.

A sequenced CBT-E → MET protocol with readiness benchmarks built into a clinical decision support tool.

1

CBT-E Foundation

  • Stabilize behaviours & health
  • Normalize eating patterns
  • Cognitive restructuring
2

Readiness Benchmarks

  • Behavioural frequency
  • Cognitive flexibility
  • Distress tolerance
3

Mirror Exposure Therapy

  • Technology-integrated
  • Reproducible module
  • Graded exposure protocol

Stepped-Care Readiness Algorithm — Click criteria to toggle readiness

Behavioural
Compensatory behaviour frequency at target (<2x/week for 4+ weeks)
Cognitive
Flexibility indicators met (EDE-Q overvaluation subscale <4.0)
Emotional
Distress tolerance within threshold (can tolerate 5+ min body exposure)
Nutritional
BMI stable in healthy range for 4+ consecutive weeks and consistent regular eating behaviours
Readiness to Progress0%

Toggle criteria above to assess phase-transition readiness.

Multi-method tracking on an app. Insights for patients + Clarity for clinicians.

Patient App Experience

Weekly Check-In
How are you feeling this week?
Log Behaviours — tap to toggle
Binge / Purge
Laxative Use
Exercise
AI / Social Media

Clinician Dashboard

Symptom Trends
Behaviour Frequency
Readiness
72%
Risk Alerts
Moderate

From Patient Input to Better Outcomes

Patient Input

(Weekly)
  • EDE-Q, PHQ-9, EAT-40
  • Behaviour logs
  • Functional check-ins

Integration

(Automated)
  • HIPAA-compliant
  • Real-time sync
  • Multi-source

Dashboard

(Longitudinal)
  • Trend visualization
  • Readiness indicators
  • Risk flags

Decision Support

(Algorithm)
  • Phase advancement
  • Escalation alerts
  • Stepped-care

Better Outcomes

(Sustained)
  • Timely adjustments
  • Reduced attrition
  • Stronger recovery

Adaptive, Technology-Integrated ED Treatment Protocol

Patient-centered design with clinician-facing decision support

Intelligent Treatment Engine

Real-Time Data

Symptom, behaviour, functioning

Clinician Decisions

Guided by evidence & context

Adaptive Algorithm

Adjusts focus + pacing and adapts exposure level

Patient
Empowered + Supported
Digital AssessmentMET InterventionsIn-App ExposuresRecovery TasksResponse PreventionFeedback LoopCBT-E SkillsMindfulness ExercisesDistress Tolerance Activities

Clinician Command Center

Live Dashboard

Track progress & trends

Risk Monitoring

Flag escalation early

Readiness Signals

Know when to advance phases

Safer Care

Early risk detection

Smarter Care

Data-driven decisions

Stronger Engagement

Between-session support

Sustained Recovery

Long-term impact