Illness duration and treatment outcome of intensive cognitive‐behavioral therapy in adolescents with anorexia nervosa

Abstract

ObjectiveThis study aimed to compare the effectiveness of an intensive treatment based on enhanced cognitive‐behavioral therapy (CBT‐E) in patients aged between 12 and 18 years with anorexia nervosa with a duration of illness <3 versus ≥3 years.MethodsOne hundred and fifty‐nine consecutively treated patients (n = 122 with illness duration <3 years and n = 37 ≥ 3 years) were enrolled in a 20‐week intensive CBT‐E program. All patients underwent assessment at admission, end of treatment (EOT), and 20‐week follow‐up. The following measures were used: body mass index (BMI)‐for‐age percentile and percentage of expected body weight (EBW), Eating Disorder Examination Questionnaire, Brief Symptom Inventory, and Clinical Impairment Assessment.ResultsApproximately 81% of eligible patients began the program, with over 80% successfully completing it. Patients with a longer or shorter duration of illness did not show significantly different treatment outcomes. In detail, BMI‐for‐age percentile and percentage of EBW outcomes were significantly improved from baseline to EOT, remaining stable until 20‐week follow‐up in both groups. Similarly, in both groups, scores for eating disorder psychopathology, general psychopathology, and clinical impairment decreased significantly at EOT and remained stable from EOT to follow‐up. Furthermore, a substantial percentage of adolescents in both groups achieved a good BMI outcome at EOT and 20‐week follow‐up, with approximately 60% maintaining a full response at the latter time point.DiscussionThese findings suggest that intensive CBT‐E appears to be an effective treatment for severely ill adolescent patients with anorexia nervosa, regardless of whether the duration of illness is shorter or longer than 3 years.Public SignificanceExisting treatment outcome studies in adolescents, whether randomized controlled trials or longitudinal investigations, typically involve patients with less than 3 years of illness, while data on the treatment outcomes for adolescents with anorexia nervosa with an illness duration of 3 years or over is very limited. Our findings suggest that adolescents with anorexia nervosa, irrespective of the duration of their illness, can derive similar benefits from intensively CBT‐E.