Obsessive-compulsive disorder with delusions.

Obsessive-compulsive (OCD) and delusional disorders (DD) have been recognised with increased frequency in recent years, and the propensity of some OCD subjects to become deluded has become a focus of interest. This study reports illness-specific demography along with measures of symptom severity and tests to assess schizotypal ideation, dysfunctional attitudes, attributional and attention bias in 30 patients with OCD, 29 with DD, 16 with OCD with delusions (OC-DD) and a 30-subject control group (CG). Obsessional features appeared before delusions in the OC-DD group, suggesting that OCD was the primary pathology. Delusions were more likely in subjects obsessional about one rather than multiple themes. There was some support for proposals that depression and schizotypy may bring out delusions in OCD and some evidence for the utility of categorising OCD according to the number of obsessions a subject has.