Outcome of severe obsessive-compulsive disorder with schizotypal features: A pilot study

Background/Purpose: Long-term outcome of patients with severe obsessive-compulsive disorder (OCD) and schizotypal features has been rarely studied. We investigated this issue in this retrospective pilot study. Methods: Twenty-two patients with severe OCD and schizotypal features were identified by chart review. Another 22 OCD patients without schizotypal features (OCD-NS) served as the comparison group. Those with schizotypal features must not fulfill a diagnosis of schizophrenia or schizotypal disorder. After an average follow-up of 6.6 years, each patient received a re-diagnosis clinical interview. Relevant demographic and clinical data were collected. Patients with schizotypal features were classified into two groups after rediagnosis: those with schizophrenia or schizotypal disorder (OCD-SS group, n = 9) and those with only schizotypal traits (OCD-ST group, n = 13) that did not fulfill a well-formed schizophrenia-spectrum disorder. Demographic data, family history, clinical symptoms, and OCD course were compared among the three patient groups. Results: Compared with the OCD-NS group, the OCD-SS group was significantly less educated, less likely to be married or female, and had earlier onset of illness and poorer OCD course (p < 0.05). There was no significant difference in any demographic and clinical variables between the OCD-SS and OCD-ST groups except that the OCD-ST group had a significantly better OCD course (p < 0.01). Conclusion: The findings suggest that a substantial proportion of the patients with severe OCD and schizotypal features evolve into schizophrenia spectrum disorder and are associated with a poor long-term outcome, whereas the OCD-NS group might stay with limited manifestations of schizotypal features and have a better outcome.