Online Behaviour Therapy Based on Exposure with Response Prevention for adults with Tourette Syndrome or Chronic Tic Disorder: A Feasibility Trial

Objective: To evaluate the feasibility, acceptability, safety, preliminary efficacy, and preliminary maintenance of TICNET, an online therapist-guided exposure and response prevention (ERP) for adults with Tourette syndrome or chronic tic disorder (TS/CTD).Design: Single-group, unmasked feasibility trial.Setting: A psychiatric outpatient clinic specialized in obsessive-compulsive and related disorders in Stockholm, Sweden.Participants: Adult participants with TS/CTD were recruited nationwide by means of self- and clinical referrals.Interventions: The 10-week online, ERP-based, therapist-supported programme TICNET consisted of eight chapters provided on a secure platform.Primary and secondary outcome measures: The RE-AIM framework (Reach, Efficacy, Adoption, Implementation, and Maintenance) was used to assess feasibility and acceptability. Safety was measured with an adverse events questionnaire. Preliminary intervention effects on tic severity were measured with the Yale Global Tic Severity Scale – Total Tic Severity subscale. Outcome measures were collected at pre- and post-treatment, as well as at the 3-, 6- and 12-month follow-up.Results: Out of 73 screened participants, 31 met inclusion criteria, with the most common reason for exclusion being not fulfilling the diagnostic criteria for TS/CTD. The participants completed an average of 6.5 out of 8 treatment chapters and 90% were classified as treatment completers. The therapists spent an average of 18.1 minutes/week supporting each participant. No serious adverse events were reported. The decrease in tic severity from pre- to post-treatment was statistically significant (Cohen’s d = 0.49, 95% CI -0.46 to 1.44), and continued to decrease further during the follow-up (12-month follow-up Cohen’s d = 1.09, 95% CI 0.14-2.04).Conclusions: TICNET is a feasible, acceptable, safe, and potentially efficacious and durable treatment for adults with TS/CTD. The treatment warrants further testing in a well-powered, randomised controlled trial with an active comparator.Trial registration: ClinicalTrials.gov (NCT04908969).