Assessment of obsessive-compulsive disorder comorbidity and obsessive-compulsive symptom dimensions in patients with schizophrenia

Objectives: To assess obsessive-compulsive disorder (OCD) comorbidity and obsessive-compulsive symptom (OCS) dimensions in patients with schizophrenia. Methods: This cross-sectional study included 300 patients with schizophrenia who were applied to the to the Outpatient Psychiatry Clinic of Health Sciences University Diskapi Yildirim Beyazit Training and Research Hospital, Ankara, Turkey between July and December 2018. Data collection forms created by researchers were applied to the individuals. Obsessive-compulsive symptom were assessed with the Yale-Brown Obsessive Compulsive Scale (YBOCS) and the Dimensional Obsessive Compulsive Scale (DOCS). Results: The OCD prevalence was 17% (n=50) in the whole group while 10% (n=24/250) of the patients without OCD had 8-15 points at YBOCS. One-way ANOVA test revealed that the patients with OCD showed more severe positive, negative, and depressive symptoms, and also had lower functionality compared to those without OCD (p<0.05). The most severe OCS dimension was unacceptable obsessional thoughts in the patients with OCD and OCS. The severity of unacceptable obsessional thoughts was positively correlated with the depressive symptom severity, and negatively correlated with onset age of OCD and insight level in Pearson correlation analysis. Conclusion: Patients with schizophrenia should be evaluated for presence of the OCS/OCD comorbidity in clinical practice. In addition, dimensional assessment of OCS might provide a different viewpoint on the presence of OCS/OCD in schizophrenia.