Randomised controlled trial of integrated cognitive behavioural treatment and motivational enhancement for comorbid social anxiety and alcohol use disorders.

Abstract

Alcohol use disorder and social anxiety disorder are interconnected disorders that commonly co-occur. We report the first trial to assess whether integrated treatment for social anxiety and alcohol use disorder comorbidity improves outcomes relative to standard alcohol-focussed treatment. Participants were recruited to a randomised controlled trial, and randomly allocated to one of two treatments, Integrated (n = 61) or Control (alcohol-focussed; n = 56). Assessment and treatment session were conducted at two sites in Sydney, Australia. Inclusion criteria were as follows: (1) clinical diagnosis of social anxiety disorder and (2) Diagnosis or sub-clinical symptoms of alcohol use disorder. Diagnoses were determined according to the Diagnostic and Statistical Manual of Mental Disorders (4th ed.). All participants (n = 117) received 10 sessions of cognitive behavioural treatment and motivational enhancement. The Integrated treatment simultaneously targeted social anxiety disorder, alcohol use disorder and the connections between these disorders. The Control treatment focussed on alcohol use disorder only. Outcomes were assessed at 6-month follow-up, with interim assessments at post-treatment and 3 months. Primary outcomes were social anxiety disorder severity (composite Social Phobia Scale and Social Interaction Anxiety Scale), alcohol use disorder severity (standard drinks per day and Severity of Alcohol Dependence Questionnaire) and quality of life (Short-Form Health survey) was assessed to capture the combined impairment of social anxiety and alcohol use disorder comorbidity. At 6-month follow-up, both conditions showed significant reductions in social anxiety and alcohol use disorder symptoms, and improved quality of life. There was no evidence of between-condition differences for alcohol outcomes, with mean consumption reduced by 5.0 (0.8) and 5.8 (1.0) drinks per day following Alcohol and Integrated treatments, respectively. Integrated treatment achieved greater improvements in social anxiety symptoms (mean difference = -14.9, 95% confidence interval = [-28.1, -1.6], d = 0.60) and quality of life (mean difference = 7.6, 95% confidence interval = [1.2, 14.0], d = 0.80) relative to alcohol-focused treatment. These results suggest that integrated social anxiety and alcohol use disorder treatment enhances quality of life and social anxiety disorder symptom improvement, but not alcohol outcomes, compared to treatment focussed on alcohol use disorder alone.