Does comorbid major depressive disorder influence outcome of exposure and response prevention for OCD?

Studies that have examined the effects of comorbid depression on response t o treatment in obsessive-compulsive disorder (OCD) have yielded inconsisten t results. We examined treatment outcome for 15 OCD patients with comorbid major depressive disorder (MDD) and 33 OCD patients without MDD. All patien ts received intensive cognitive-behavioral therapy by exposure and response (ritual) prevention. Improvement in OCD symptoms was observed in both pati ent groups, and treatment gains were maintained at follow-up. Whereas the p resence of a comorbid MDD diagnosis in OCD was not related to treatment fai lure, nondepressed patients had significantly lower posttreatment and follo w-up OCD severity scores.