Relapse Rates in Anorexia Nervosa in Young People
Relapse rates in young people with anorexia nervosa range from 9% to 52%, with the highest risk occurring within the first year after treatment, particularly between 6 to 17 months post-discharge. 1, 2
Understanding Relapse Rates and Timing
The substantial variation in reported relapse rates (9-52%) reflects inconsistent definitions across studies, but there is clear consensus that relapse risk increases with longer follow-up duration 1. The critical vulnerability period extends through the first 18 months after weight restoration, with mean survival time (time to relapse) being approximately 18 months 2.
The first year following treatment represents the most dangerous period for relapse, requiring intensive monitoring and support. 1, 2
Risk Factors That Predict Relapse
Several factors significantly increase relapse risk in young people:
Psychiatric and Treatment History
- History of suicide attempts is a strong predictor of relapse 2
- Previous specialized eating disorder treatment indicates elevated risk 2
- Severity of obsessive-compulsive symptoms at initial presentation predicts relapse 2
Post-Treatment Factors
- Residual concern about shape and weight at discharge significantly increases relapse risk 2
- Excessive exercise immediately after discharge is a critical warning sign 2
- Longer duration of illness (>10 years) is associated with worse outcomes 3
- Lower BMI (<16 kg/m²) correlates with higher mortality and relapse risk 3
Most Effective Treatment Approaches to Reduce Relapse
Family-Based Therapy (FBT) - First-Line for Adolescents
Family-Based Therapy demonstrates superior outcomes compared to Adolescent-Focused Therapy, with higher rates of weight gain, partial remission, and full remission lasting up to 4 years. 4
The American Academy of Pediatrics recommends that parents take full control of all eating decisions and meal planning without blame or punishment, as they are vital to therapeutic success and responsible for weight restoration 5, 6. This three-phase approach involves:
- Phase 1: Parents assume complete control of refeeding and meal planning, focusing on medical stabilization and nutritional rehabilitation 6
- Phase 2: Gradual return of control to the adolescent after achieving medical stability 6
- Phase 3: Focus on broader adolescent development issues and preparation for treatment termination 6
Cognitive-Behavioral Therapy and Technology-Based Interventions
For relapse prevention specifically, computer-based interventions (CBIs) show promise, though evidence remains limited with only one study empirically evaluating this approach in AN patients 3. Email contact and mobile interventions may enhance adherence, patient satisfaction, and therapeutic alliance when used as adjuncts to regular therapy 3.
Pharmacological Considerations
Fluoxetine may help prevent relapse in weight-restored patients with anorexia nervosa. 7, 8 This represents the most promising pharmacological finding for relapse prevention, though it should only be considered after weight restoration has been achieved 8.
Critical Monitoring Requirements
Medical Instability Warning Signs
Parents and clinicians must monitor for critical warning signs, even when laboratory tests appear normal (which occurs in more than half of medically unstable adolescents) 6:
- Bradycardia: Heart rate <50 beats/minute during the day 6
- Hypotension: Blood pressure <90/45 mm Hg 6
- Hypothermia: Body temperature <96°F 6
- Orthostatic changes: Pulse increase >20 beats/min or blood pressure drop >20 mm Hg systolic on standing 6
Behavioral Red Flags
- Excessive exercise patterns immediately post-discharge 2
- Persistent preoccupation with shape and weight 2
- Return of food restriction behaviors 9
Essential Pitfalls to Avoid
Do not wait for laboratory abnormalities before taking action—normal test results do not indicate safety. 6 Most patients with eating disorders have normal laboratory results despite serious medical instability 6.
Do not assume the young person will "grow out of it"—early diagnosis and intervention are associated with improved outcomes. 6
Avoid all comments about body weight, even well-intended ones, as they can be perceived as hurtful. 6 Parental weight talk is linked to higher rates of overweight and eating disorders 6.
Do not attempt to manage the eating disorder without a multidisciplinary team. 6 The mortality rate for eating disorders is among the highest for any psychiatric disorder, with cardiac complications responsible for at least one-third of all deaths 5, 7, 6.
Structured Relapse Prevention Framework
The Guideline Relapse Prevention (GRP) for Anorexia Nervosa provides a structured approach that patients and families find valuable 9. Key components include:
- Maintaining professional contact during aftercare to support ongoing recovery 9
- Self-management strategies that patients can implement independently 9
- Enhanced understanding of personal relapse processes and triggers 9
Realistic Outcome Expectations
Despite optimal treatment with FBT or AFT, a significant proportion of young people do not achieve target weight or full remission, indicating that current treatments are not universally effective. 4 This underscores the need for intensive follow-up, early identification of relapse warning signs, and immediate intervention when concerning patterns emerge.
The overall relapse rate of 35% with highest risk between 6-17 months post-discharge means that close interval follow-up with the multidisciplinary team is mandatory during this critical period. 3, 2