Effectiveness of a Five-Day Multimodal Intensive Treatment Program for Obsessive-Compulsive Disorder: A Prospective Observational Study

Introduction: Obsessive-compulsive disorder (OCD) is a chronic psychiatric disorder that frequently requires a combination of pharmacological and behavioral interventions. Intensive treatment programs integrating optimized pharmacotherapy, exposure and response prevention (ERP), and neuromodulation have emerged as promising approaches for accelerating symptom improvement. However, evidence regarding the effectiveness of complete adherence to such multimodal interventions in routine clinical practice remains limited. This study evaluated the clinical effectiveness and safety of a five-day multimodal intensive treatment program in patients with OCD. Materials and methods: This prospective observational study included 123 adults with OCD enrolled in a standardized five-day intensive outpatient program. The participants received optimized pharmacotherapy, therapist-guided ERP, and adjunctive neuromodulation using repetitive transcranial magnetic stimulation or transcranial direct current stimulation. Based on treatment adherence, participants were categorized into full (n = 45) and partial (n = 78) triad groups. The primary outcome was the change in Obsessive-Compulsive Inventory (OCI) scores from baseline to Day 5 and four-week follow-up. Secondary outcomes included treatment adherence characteristics and treatment-related adverse events. Independent-samples t-tests, chi-square tests, or Fisher’s exact tests, as appropriate, were used for between-group comparisons, while analysis of covariance (ANCOVA) was performed to compare Week-4 Yale-Brown Obsessive Compulsive Scale (Y-BOCS) scores after adjustment for baseline Y-BOCS score and age. Statistical significance was set at p < 0.05. Results: The two groups were similar in baseline clinical and demographic features. The full triad group demonstrated significantly greater reductions in OCI scores than the partial triad group at both the five- and four-week follow-up (both p < 0.001). Participants with complete adherence also completed significantly more ERP and neuromodulation sessions and showed higher homework compliance (all p < 0.001). After adjusting for baseline OCI score and age, treatment adherence remained an independent predictor of Week-4 OCI outcomes (p < 0.001). There were no appreciable variations in treatment-related complications, and the frequency of adverse events was similar among the groups. Conclusions: A five-day multimodal intensive treatment program combining optimized pharmacotherapy, ERP, and neuromodulation was associated with significant short-term improvements in OCD symptoms and demonstrated a favorable safety profile. Complete adherence to all treatment components is associated with superior clinical outcomes, highlighting the importance of comprehensive participation in intensive multimodal treatment programs for OCD.