Current status and features of antipsychotic prescriptions in Japanese forensic psychiatric wards based on a forensic inpatient database.

Aim: Psychopharmacotherapy plays an important role in the treatment of mentally disordered offenders (MDOs) with schizophrenia spectrum disorders. However, there have been few large-scale reports from multiple forensic psychiatric wards. This study aimed to clarify the current state of antipsychotic medications for MDOs with schizophrenia spectrum disorders in Japanese forensic psychiatric wards.

Methods: Medical information, including age, sex, psychiatric diagnosis, index offense, seclusion or restraint experience during hospitalization, and medication for patients discharged from 32 forensic wards nationwide between September 1, 2019 and December 31, 2021 was provided by the Database Scientific Utilization Project of Japanese forensic psychiatric wards. We analyzed the data of MDOs with schizophrenia spectrum disorders who were prescribed psychotropic medications at the time of discharge, especially focusing on comparing differences between the three groups (clozapine, long-acting injection (LAI), and other medications).

Results: A total of 362 MDOs with schizophrenia spectrum disorders were prescribed psychotropic medications at discharge. The prescription rates of clozapine and LAI were 23.2% and 24.9%, respectively. Additionally, the rate of antipsychotic polypharmacy was 37.8%. Among the three groups, the clozapine group had the highest rate of seclusion experience (46.4%), a long mean length of hospitalization (1758 days), and the lowest rate of antipsychotic polypharmacy (4.8%). Olanzapine was the most commonly prescribed antipsychotic medication.

Conclusion: This study revealed the current state of antipsychotic medications for MDOs admitted to forensic psychiatric wards in Japan. Future studies are needed to clarify the relevance of antipsychotic medications in the prognosis of MDOs.