2026 ECNP Congress

PS01-1056

Early intervention in anorexia nervosa: a case series of three adolescents

Emine Ayhan — Y.G. Uluman, H. Ünver · Marmara University School of Medicine, Department of Child and Adolescent Psychiatry, İstanbul, Türkiye

2026 ECNP Congress

Background

A prolonged duration of untreated eating disorder (DUED) is associated with poorer treatment response and a higher risk of chronicity in anorexia nervosa (AN). The mean DUED for AN is approximately 30 months internationally, and early-stage illness (<3 years) shows a markedly better treatment response than longer-standing disease (Austin et al., 2021). In adolescents, the threshold for intervention should be even lower given the potentially irreversible impact of malnutrition on growth, sexual maturation and bone mineralisation (Society for Adolescent Medicine, 1998). These observations have motivated specialised early-intervention service models such as FREED (First Episode Rapid Early Intervention for Eating Disorders): approximately 60% of FREED AN patients reach a healthy BMI at 12 months versus only ~17% in treatment-as-usual, with a ~36% reduction in inpatient/day-patient need (Flynn et al., 2020; Grycuk et al., 2025). Drawing on these principles, we present three adolescent AN cases to illustrate the impact of DUED on clinical course.

Methods

Medical records of three patients (age range 14–17 years) with a DSM-5 diagnosis of AN, followed at our Child and Adolescent Psychiatry outpatient clinic, were retrospectively reviewed. Baseline and follow-up body mass index (BMI), DUED (defined as the time in months from illness onset to first evidence-based treatment), treatment modality and clinical outcome were extracted. Written informed consent was obtained and data were anonymised.

Cases

Case 1 (favourable course): 16-year-old female, DUED 7 months, baseline BMI 17.8 kg/m², restricting-type AN. Treated with outpatient cognitive behavioural therapy (CBT) and pharmacotherapy (fluoxetine 20 mg, aripiprazole 5 mg). At 5-month follow-up, BMI rose to 20.6 kg/m²; dietary adherence and body image improved. Outcome: clinical remission.

Case 2 (favourable course): 14-year-old female, DUED 6 months, baseline BMI 18.8 kg/m², binge-eating/purging subtype AN. Treated with outpatient CBT and pharmacotherapy (fluoxetine 20 mg, olanzapine 2.5 mg). At 8-month follow-up, BMI reached 21.6 kg/m²; self-induced vomiting ceased and body image distortion markedly improved. Outcome: clinical remission.

Case 3 (substantial improvement): 17-year-old female, DUED 30 months, baseline BMI 13.3 kg/m², with comorbid anxiety disorder, mitral valve prolapse and menstrual irregularity. Treated with outpatient CBT and pharmacotherapy (escitalopram 15 mg, olanzapine 2.5 mg). At 18-month follow-up, BMI rose to 16.4 kg/m²; nausea and vomiting episodes were markedly reduced and body image improved. Outcome: partial response with meaningful functional recovery.

Discussion and Conclusion

This case series illustrates the determining role of DUED in the clinical course of AN: the two patients presenting with a short DUED achieved full remission with outpatient care, whereas the patient with a longer DUED achieved only partial response despite sustained treatment. These observations are consistent with the international literature and underscore the relevance of adolescent-specific early-intervention pathways that address both patient-related (problem recognition, ambivalence, help-seeking barriers) and service-related components of DUED, consistent with the FREED model principles — rapid triage, short waiting times and developmentally adapted, interdisciplinary care. The first three years of illness represent a critical window in which specialist intervention has the greatest potential to alter prognosis. The retrospective design, single-centre setting and small sample size limit causal inference.

Keywords

anorexia nervosa; early intervention; duration of untreated illness; DUED; adolescent.

References

  1. Austin A, Flynn M, Richards K, et al. Duration of untreated eating disorder and relationship to outcomes: A systematic review of the literature. Eur Eat Disord Rev. 2021;29(3):329–345.
  2. Society for Adolescent Medicine. Eating disorders in adolescents: Principles of diagnosis and treatment (CPS Clinical Practice Guideline AM 96-04). Paediatr Child Health. 1998;3(3):189–192.
  3. Flynn M, Austin A, Lang K, et al. Assessing the impact of First Episode Rapid Early Intervention for Eating Disorders on duration of untreated eating disorder: A multi-centre quasi-experimental study. Eur Eat Disord Rev. 2021;29(3):458–471. doi:10.1002/erv.2797
  4. Grycuk L, Monssen D, Davies MR, et al. Shortening duration of untreated illness in young people with first episode eating disorders: protocol of a randomised controlled feasibility trial of a smartphone friendly multi-modal decision-making tool (FREED-M). Pilot Feasibility Stud. 2025;11:14.