Relationship between antipsychotic medication and aggressive events in patients with a psychotic disorder hospitalized for treatment

BACKGROUND: Disruptive and aggressive behavior is frequent in patients with a psychotic disorder; furthermore, it is a recurrent reason for compulsory admission. Even during treatment, many patients continue to show aggressive behavior. Antipsychotic medication is posed to have anti-aggressive properties; its prescription is a common strategy for the treatment (and prevention) of violent behavior. The present study aims to investigate the relation between the antipsychotic class, according to the dopamine D2-Receptor binding affinity (i.e., “loose” – “tight binding”), and aggressive events perpetrated by hospitalized patients with a psychotic disorder. METHODS: We conducted a four-year retrospective analysis of legally liable aggressive incidents perpetrated by patients during hospitalization. We extracted patients’ basic demographic and clinical data from electronic health records. We used the Staff Observation Aggression Scale (SOAS-R) to grade the severity of an event. Differences between patients with a “loose” or “tight-binding” antipsychotic were analyzed. RESULTS: In the observation period, there were 17,901 direct admissions; and 61 severe aggressive events (an incidence of 0.85 for every 1,000 admissions year). Patients with a psychotic disorder perpetrated 51 events (incidence of 2.90 for every 1,000 admission year), with an OR of 15.85 (CI: 8.04–31.25) compared to non-psychotic patients. We could identify 46 events conducted by patients with a psychotic disorder under medication. The mean SOAS-R total score was 17.02 (2.74). The majority of victims in the “loose-binding” group were staff members (73.1%, n = 19), while the majority of victims in the “tight-binding” group were fellow patients (65.0%, n = 13); (X(2)(3,46) = 19.687; p < 0.001). There were no demographic or clinical differences between the groups and no differences regarding dose equivalents or other prescribed medication. CONCLUSIONS: In aggressive behaviors conducted by patients with a psychotic disorder under antipsychotic medication, the dopamine D2-Receptor affinity seems to have a high impact on the target of aggression. However, more studies are needed to investigate the anti-aggressive effects of individual antipsychotic agents.