Predictors of treatment outcome in modular cognitive therapy for obsessive-compulsive disorder

Background: The present study sought to identify predictors of outcome for a comprehensive cognitive therapy (CT) developed for patients with obsessive-compulsive disorder (OCD). Methods: Treatment was delivered over 22 sessions and included standard CT methods, as well as specific strategies designed for subtypes of OCD including religious, sexual, and other obsessions. This study of 39 participants assigned to CT examined predictors of outcomes assessed on the Yale-Brown Obsessive Compulsive Scale. A variety of baseline symptom variables were examined as well as treatment expectancy and motivation. Results: Findings indicated that participants who perceived themselves as having more severe OCD at baseline remained in treatment but more severe symptoms were marginally associated with worse outcome for those who completed therapy. Depressed and anxious mood did not predict post-test outcome, but more Axis I comorbid diagnoses (mainly major depression and anxiety disorders), predicted more improvement, as did the presence of sexual (but not religious) OCD symptoms, and stronger motivation (but not expectancy). A small rebound in OCD symptoms at 1-year follow-up was significantly predicted by higher scores on personality traits, especially for schizotypal (but not obsessive-compulsive personality) traits. Conclusions: Longer treatment may be needed for those with more severe symptoms at the outset. CT may have positive effects not only on OCD symptoms but also on comorbid depressive and anxious disorders and associated underlying core beliefs. Findings are discussed in light of study limitations and research on other predictors.