Efficacy of Exposure and Response Prevention(ERP) and SSRIs in Chinese OCD Patients

The purpose of this study is to evaluate the efficiency of SSRIs（Selective Serotonin Reuptake Inhibitor） ,ERP（Exposure and Response Prevention） and the combination of the two therapies for OCD(Obsessive-Compulsive Disorder) patients ,at the same time, to find out the biological or psychological predictors of treatment response in Chinese population.

Although Selective Serotonin Reuptake Inhibitors(SSRIs) and Cognitive Behavior Therapy (CBT) including Exposure and Response Prevention(ERP) are two kinds of the first line treatments for OCD(Obsessive-Compulsive Disorder) according to APA（American Psychological Association）guideline. Both of the treatments are effective, but few research has been done to find out who are more responsive to one treatment than the other. The aim of our research is to evaluate the efficiency of SSRIs ,ERP and the combination of the two therapies for OCD patients ,at the same time, to find out the biological and psychological predictors of treatment response in Chinese population.

This is a randomized, single-blind, cross-over design study.Approximately 60 patients will be randomized to SSRIs or ERP group. Neuropsychological assessment and fMRI(Functional Magnetic Resonance Imaging） will be performed at baseline,during the treatment and at the end of the study. The research has two period. In the first period(before week 8) ,the patients will have monotherapy. In the second period(after week 8), rates of improvement based on the YBOCS(Yale-Brown Obsessive Compulsive Scale) scores will be assessed. The patient will be considered responsive to treatment when he or she has a reduction in YBOCS score ≥ 35% of the score at the baseline.If the patient is responsive to the treatment that he or she has received at the first 8 weeks,he or she will continue to follow the previous treatment strategy.If not,the patient will have a combination of SSRIs and ERP treatment for another 8 weeks. The follow-up period will last up to 6 months.The result of the study will improve our knowledge about the efficacy of the two first line treatments .Also,it will help us to find out the predictors of the outcome of the two different kinds of treatments.Strategy of clinical treatment of OCD will be more individualized in the future.

Eligibility Criteria:
Inclusion Criteria:

* Having been diagnosed with primary OCD as defined by the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV-) criteria;Cleaning or checking as primary OCD symptoms
* Yale-Brown Obsessive-Compulsive Scale (Y-BOCS) score of ≥ 16
* Never receiving adequate treatment or stop receiving treatment for at least 8 weeks
* Having an education degree of high school or above
* Accepting to participate in the study

Exclusion Criteria:

* Having significant medical illnesses that would interfere with the conduct of the study
* Clinically significant abnormal laboratory finding
* Having comorbid psychiatric conditions according to the criteria set forth in the DSM-IV(administered by the Mini-International Neuropsychiatric Interview (MINI))
* The current OCD symptoms are too severe that the patient cannot finish the evaluation or receive the ERP
* Being currently at risk for suicide
* Being pregnant or having the intention to be pregnant before the end of the study
* A history of having inadequate response to adequate SSRIs or CBT treatment
* Subjects who are unable to undergo the MRI