Dissociation in schizophrenia and borderline personality disorder

BACKGROUND Dissociation likely plays a key role in schizophrenia and borderline personality disorder (BPD), although empirical studies that compare specific manifestations of these symptoms in schizophrenia and BPD are rare. In this context, the purpose of this study was to compare the occurrence of dissociative and other psychopathological symptoms in these disorders, and to assess the possible influence of antipsychotic medication on the dissociative symptoms. METHODS We assessed 31 patients with schizophrenia and 36 patients with BPD. Dissociative symptoms were measured by the Dissociative Experiences Scale (DES), symptoms related to stress and traumatic experiences were assessed using the Trauma Symptom Checklist-40 (TSC-40), and other psychopathological symptoms were measured with the Health of the Nation Outcome Scales (HoNOS). We also assessed actual daily doses of antipsychotic medication in chlorpromazine equivalents in all participants. RESULTS The results show that symptoms of traumatic stress measured by the TSC-40 had significantly higher scores in the BPD group. The data also show that dissociative symptoms (DES) were significantly correlated with symptoms of traumatic stress (TSC-40) and with symptoms assessed by the HoNOS. Remarkably significant correlations were found between levels of antipsychotic medication and the DES and between antipsychotic medication and the depersonalization/derealization component of the DES in BPD patients. CONCLUSION The results support an important role of dissociative processes in schizophrenia and BPD and suggest a significant relationship between manifestations of dissociative symptoms in BPD and antipsychotic medication.