Does completion of 12 months of treatment show improved outcomes? A case series from an adult dialectical behaviour therapy programme for multi-diagnostic eating disorders (MED-DBT).

Dialectical behaviour therapy (DBT) has a developing evidence base for treating complex multi-diagnostic eating disorder presentations, including for individuals with long-standing eating disorders. A retrospective analysis of pre- and post-test data collected at 12 months from 16 adult participants in a "DBT for Multi-diagnostic Eating Disorders" (MED-DBT) programme run in New Zealand was conducted. Psychological outcomes were assessed using the Depression, Anxiety and Stress Scale-21 (DASS-21) and Difficulties with Emotion Regulation Scale (DERS). Clinical indicators consisted of body mass index (BMI) and scores on the Eating Disorder Examination Questionnaire (EDE-Q). Significant differences were found for difficulties with emotion regulation scores (U = 8.571, p = .007), eating disorder examination questionnaire global scores (U = 47.5, p = .003), and anxiety scores (U = 42.0, p = .040), favouring those who completed the 12 months of the MED-DBT programme including the skills group. No significant differences were found for depression or stress symptoms. BMI increased for those who completed 12 months of the programme (Mdn = 1.265) and decreased (Mdn = -.580; U = 6.0, p = .019) for non-completers. The findings suggest that completing 12 months of MED-DBT including the group component may result in clinically meaningful change when compared to non-completion. Although participants were still experiencing eating disorder symptoms at the end of 12 months, these were significantly reduced and were paired with improved emotional wellbeing.