Effectiveness and Changes in Brain Functions by an Occupational Therapy Program Incorporating Mindfulness in Outpatients with Anxiety and Depression: A Randomized Controlled Trial

Introduction: This study examined the efficacy of an 8-week occupational therapy program incorporating mindfulness (MOT) as a form of psychiatric rehabilitation to ameliorate residual social and occupational impairment in patients with anxiety disorders and depression. The objective was to evaluate the effects of MOT on their personal well-being and to assess the impact of MOT on brain function using quantitative electroencephalography (qEEG). Methods: This study was a randomized, wait-list control trial with assessments performed at baseline, post-intervention (9 weeks), and follow-up (18 weeks) in outpatients with anxiety disorders and depression. The MOT was conducted in small groups, comprising eight weekly 1.5-h sessions. The primary outcome was the mean score change between the pre- and post-interventions with Questionnaire about the Process of Recovery (QPR) scale. Other clinical assessments and qEEG served as secondary and biological outcomes, respectively. Results: A total of 25 patients (mean age: 44.1) were included in the analysis. The MOT group demonstrated a significantly improved QPR compared to the control group after adjusting for baseline covariates (p < 0.01). This improvement was sustained for 9 weeks after the 8-week intervention. In the qEEG analysis, a significant increase in current source density in the β2 band of the left dorsolateral prefrontal cortex was observed in the MOT group compared to the control group (p < 0.02). Conclusion: This study demonstrates that MOT improves subjective well-being and potentially, global function. This suggests that MOT may serve as a viable option for those whose symptoms have abated but who still struggle with social and occupational functioning.