What is the recommended treatment approach for anorexia nervosa in individuals under 18 years?

Treatment of Anorexia Nervosa in Individuals Under 18 Years

Adolescents and emerging adults with anorexia nervosa who have an involved caregiver should be treated with eating disorder-focused family-based treatment (FBT) as the first-line approach. 1

Primary Treatment Approach: Family-Based Treatment

Family-based treatment is the gold-standard intervention for adolescents with anorexia nervosa, with the American Psychiatric Association providing a strong recommendation (1B rating) specifically for this age group. 1

Core Components of FBT

• Caregiver education and empowerment to normalize eating and weight control behaviors and restore weight is the central mechanism of FBT. 1

• Three-phase structure guides treatment: Phase 1 focuses on parental management of refeeding at home, Phase 2 gradually returns eating control to the adolescent, and Phase 3 addresses broader adolescent developmental tasks. 2

• Weight restoration targets must be individualized with specific weekly weight gain goals and target weights set for each patient requiring nutritional rehabilitation. 1

Evidence Supporting FBT Superiority

• FBT demonstrates superior long-term outcomes compared to adolescent-focused individual therapy, with significantly higher full remission rates at 6-month (FBT superior) and 12-month follow-up (FBT superior), despite similar end-of-treatment results. 3

• Treatment duration typically involves 18-24 sessions over 6-12 months in the outpatient setting for medically stable adolescents. 3, 4

Alternative Delivery Models

Parent-Focused Treatment (PFT)

• PFT involves meeting with parents only while a nurse monitors the adolescent separately, and showed higher remission rates than standard FBT at end of treatment (43% vs 22%, OR=3.03), though differences diminished at follow-up. 4

• This approach may be particularly useful when family conflict is high or when the adolescent strongly resists conjoint sessions. 4

Guided Self-Help FBT

• Online guided self-help FBT using approximately 25% of standard therapist time (10 twenty-minute sessions vs 15 sixty-minute sessions) appears feasible and acceptable, with preliminary data showing median BMI improvement from 85% to 97% at end of treatment. 5, 6

• Dropout rates of 21% during treatment and 33% during follow-up suggest adherence challenges that require monitoring. 6

Essential Medical Assessment and Monitoring

Initial Evaluation Requirements

• Vital signs assessment including temperature, resting heart rate, blood pressure, orthostatic pulse, and orthostatic blood pressure must be documented. 1

• Anthropometric measurements should use percent median BMI, BMI percentile, or BMI Z-score rather than standard BMI for children and adolescents. 1

• Laboratory assessment requires complete blood count and comprehensive metabolic panel including electrolytes, liver enzymes, and renal function tests. 1

• Electrocardiogram is mandatory in patients with restrictive eating disorders, severe purging behavior, or those taking QTc-prolonging medications. 1

Ongoing Monitoring

• Quantify eating and weight control behaviors including frequency, intensity, and time spent on dietary restriction, binge eating, purging, exercise, and other compensatory behaviors at each visit. 1

• Screen for co-occurring psychiatric disorders as part of comprehensive assessment, since comorbidity is common and affects treatment planning. 1

Multidisciplinary Team Coordination

• Treatment requires documented coordination among medical, psychiatric, psychological, and nutritional expertise throughout the entire treatment duration. 1, 7

• The team should include a primary care physician, mental health practitioner skilled in eating disorders, and registered dietitian working in a coordinated fashion. 1

Critical Clinical Considerations

Treatment Barriers

• Shame, stigma, and shortage of specialized providers can interrupt or prolong treatment and must be proactively addressed through psychoeducation and treatment engagement strategies. 7

• Technology-based interventions via videoconferencing may help overcome geographic barriers for families living far from specialized eating disorder treatment centers. 8, 5

Broader Developmental Context

• FBT addresses the full range of psychopathology beyond weight restoration, including temperament traits, emotional processing, cognitive distortions, social functioning, and family dynamics throughout all three phases. 2

• The approach recognizes that starvation-related cognitions and behaviors interfere with normal adolescent development, requiring weight restoration as the foundation before fully addressing broader developmental tasks. 2

Common Pitfalls to Avoid

• Do not delay treatment waiting for the adolescent to be "motivated" - FBT empowers parents to initiate refeeding regardless of the adolescent's initial resistance. 2

• Do not treat adolescents with the same approaches used for adults - the evidence specifically supports family-based approaches for this age group rather than individual psychotherapy as first-line treatment. 1

• Do not underestimate medical instability - even outpatients require careful monitoring of vital signs and laboratory parameters throughout weight restoration. 1