Obsessive-compulsive disorder and obsessive-compulsive symptoms in Japanese inpatients with chronic schizophrenia – A possible schizophrenic subtype

To investigate the prevalence of obsessive-compulsive disorder (OCD) and obsessive-compulsive symptoms (OCS) and their association with demographic and clinical factors, 92 inpatients with chronic schizophrenia participated in this study. Demographic factors, severity of psychiatric symptoms as determined by Brief Psychiatric Rating Scale and OCS by Yale–Brown Obsessive Compulsive Scale, general functioning, extrapyramidal symptoms, and dose of antipsychotics were compared between patients with and without OCD or OCS. The Mini-International Neuropsychiatric Interview was employed for diagnosis of OCD and OCS. OCD and OCS were observed in 14.1% and 51.1% of inpatients with schizophrenia, respectively. Schizophrenic patients with OCS exhibited significantly earlier onset of schizophrenia, lower socioeconomic status, and more severe psychiatric symptoms than those without OCS. Earlier hospitalization of schizophrenia, family history of psychosis, and more severe schizophrenic symptoms were associated with comorbidity of OCS, as determined by logistic regression analysis, and younger age was associated with more severe OCS. However, negative symptoms were associated with comorbidity of OCD in chronic schizophrenia. Our findings suggest there is a subtype of schizophrenia with OCS, which is related to earlier onset and more severe psychotic symptoms.