Background: Family-based treatment (FBT) is an efficacious intervention for adolescents with an eating disorder. Evaluated to a lesser degree among adolescents, enhanced cognitive-behavior therapy (CBT-E) has shown promising results. This study compared the relative effectiveness of FBT and CBT-E, and as per manualized CBT-E, the sample was divided into a lower weight [<90% median body mass index (mBMI)], and higher weight cohort (⩾90%mBMI).
Method: Participants (N = 97) aged 12-18 years, with a DSM-5 eating disorder diagnosis (largely restrictive, excluding Avoidant Restrictive Food Intake Disorder), and their parents, chose between FBT and CBT-E. Assessments were administered at baseline, end-of-treatment (EOT), and follow-up (6 and 12 months). Treatment comprised of 20 sessions over 6 months, except for the lower weight cohort where CBT-E comprised 40 sessions over 9-12 months. Primary outcomes were slope of weight gain and change in Eating Disorder Examination (EDE) Global Score at EOT.
Results: Slope of weight gain at EOT was significantly higher for FBT than for CBT-E (lower weight, est. = 0.597, s.e. = 0.096, p < 0.001; higher weight, est. = 0.495, s.e. = 0.83, p < 0.001), but not at follow-up. There were no differences in the EDE Global Score or most secondary outcome measures at any time-point. Several baseline variables emerged as potential treatment effect moderators at EOT. Choosing between FBT and CBT-E resulted in older and less well participants opting for CBT-E.
Conclusions: Results underscore the efficiency of FBT to facilitate weight gain among underweight adolescents. FBT and CBT-E achieved similar outcomes in other domains assessed, making CBT-E a viable treatment for adolescents with an eating disorder.
Clinical trial registration information: Treatment Outcome in Eating Disorders; https://clinicaltrials.gov/; NCT03599921.
Keywords: Enhanced cognitive-behavior therapy; family-based treatment; restrictive eating disorders; treatment effectiveness.