The adolescent onset anorexia nervosa study (ANABEL): Design and baseline results.

The anorexia nervosa adolescent longitudinal biomarker assessment study (ANABEL) is a 2-year longitudinal study.

OBJECTIVE: Evaluate several clinical, biochemical, immunological, psychological, and family variables and their interactions in adolescent onset eating disorders (EDs) patients and their 2-year clinical and biological outcome. This article illustrates the framework and the methodology behind the research questions, as well as describing general features of the sample.

METHODS: A longitudinal study of 114 adolescents with EDs seeking treatment was performed. Only adolescents were selected during 4 years (2009-2013). The variables were collected at different times: baseline, 6, 12, 18, and 24 months of the start of treatment. Diagnoses were completed through the semi-structured Kiddie-Schedule for Affective Disorders and Schizophrenia interview.

RESULTS: At baseline, the mean age was 15.11 (SD = 1.36). The mean ED duration was 10 months (SD = 5.75). The mean body mass index was 16.1 (SD = 1.8). The Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition diagnosis at baseline for restrictive anorexia nervosa was 69.6%, 17.4% for purgative anorexia nervosa, and 24.3% for other specified feeding disorder. At 12 months, 19.4% were in partial remission, whereas at 24 months, 13.8% had fully recovered and 29.2% had partially recovered.

CONCLUSIONS: There was an acceptable physical and psychopathological improvement during the first year of treatment, with recovery being more evident during the first 6 months.