AIM: The current study examined the preliminary efficacy of dialectical behaviour therapy (DBT) adapted for concurrent eating disorders (EDs) and substance use disorders (SUDs).
METHOD: A matched randomized controlled trial was carried out with 25 female outpatients diagnosed with concurrent ED and SUD. Participants randomized to the intervention condition received DBT, whereas those randomized to the control condition received treatment as usual (TAU), both for a period of 1 year. A series of measures related to disordered eating, substance use and depression were administered to the participants at the beginning of treatment and at 3, 6, 9 and 12 months into treatment, followed by 3-month and 6-month follow-up assessments.
Participants randomized to the DBT condition evidenced a superior retention rate relative to their counterparts in the TAU condition at various study time points, including post-treatment (80% versus 20%) and follow-up (60% versus 20%). Due to the unexpected elevated dropout rates and the worsening of ED-SUD symptomatology in the TAU condition, recruitment efforts were terminated early. Results from the DBT condition revealed that the intervention had a significant positive effect on behavioural and attitudinal features of disordered eating, substance use severity and use, negative mood regulation and depressive symptoms. Finally, increases in participants' perceived ability to regulate and cope with negative emotional states were significantly associated with decreases in emotional eating and increases in levels of confidence in ability to resist urges for substance use.
CONCLUSION: Results suggest that the adapted DBT might hold promise for treating individuals with concurrent ED and SUD.
KEY PRACTITIONER MESSAGE: The current study is the first study to report positive effects of DBT on individuals with concurrent eating and substance use disorders. Although the results require replication and extension, they suggest that the DBT may be promising for this population. The results suggest that clinicians treating individuals with concurrent eating and substance use problems should be particularly cautious of poor treatment retention and treatment complications. The results bear upon the highly salient and important issue of whether individuals with concurrent substance use need to be excluded from research studies and treatment programmes.