Mindfulness-Based Cognitive Therapy for Unmedicated Obsessive-Compulsive Disorder: A Randomized Controlled Trial With 6-Month Follow-Up.

Background: This was the first randomized controlled trial (RCT) designed to compare the efficacy of mindfulness-based cognitive therapy (MBCT) on unmedicated obsessive-compulsive disorder with that of the first-line treatment for OCD (SSRIs) or a placebo, as well as to analyze the treatment acceptability and safety of MBCT. Methods: A total of 123 unmedicated OCD patients with mild to moderate symptoms were randomly assigned into selective serotonin reuptake inhibitors group (SSRIs group), MBCT group or psycho-education group (PE group), respectively. They were intervened for 10 weeks. The Yale-Brown Obsessive-Compulsive Scale (Y-BOCS) grade was the primary outcome, and Hamilton Depression Scale-24 (HAMD-24) and Hamilton Anxiety Scale (HAMA) grades were secondary outcomes to be measured at baseline, mid-intervention, post-intervention and 14, 22, and 34 weeks of follow-up. The Five Facet Mindfulness Questionnaire (FFMQ) and Sheehan Disability Scale (SDS) were used to assess mindfulness and social functions, respectively. In addition, treatment acceptability (dropout rate and frequency of occurrence) and safety [adverse event (AE)] of MBCT were investigated. Results: Significant differences were detected in the treatment responses among SSRIs group, MBCT group and PE group. Notably, treatment responses were significantly better in the former two groups than that of PE group (χ2 = 6.448, p = 0.04), although we did not identify significant differences between SSRIs group and MBCT group (χ2 = 1.220, p = 0.543). Observed until 6 months of follow-up, there were no significant differences in treatment response among three groups. No AE was recorded in MBCT group. Conclusion: MBCT is effective in the treatment of unmedicated OCD with mild to moderate symptoms comparable to that of SSRIs, which contributes to maintain the treatment outcomes at follow-up. Besides, MBCT is safe with a good clinical compliance.