Medication Use and Physical Assaults in the Psychiatric Emergency Department

Objective: To evaluate the relationship between medications used to treat acute agitation (antipsychotics, mood stabilizers, and benzodiazepines) and subsequent assault incidence in the psychiatric emergency department. Methods: Medication orders and assault incident reports were obtained from electronic health records for 17,056 visits to an urban psychiatric emergency department from 2014 to 2019. Assault risk was modeled longitudinally using Poisson mixed-effects regression. Results: Assaults were reported during 0.5% of visits. Intramuscular (IM) medications were ordered in 23.3% of visits overall and predominantly were ordered within the first 4 hours of a visit. IM medication orders were correlated with assault (incident rate ratio [IRR] = 24.2; 95% CI, 5.33-110.0), often because IM medications were ordered immediately subsequent to reported assaults. Interacted with time, IM medications were not significantly associated with reduction in subsequent assaults (IRR = 0.700; 95% CI, 0.467-1.04). Neither benzodiazepines nor mood stabilizers were associated with subsequent changes to the risk of reported assault. By contrast, antipsychotic medications were associated with decreased assault risk across time (IRR = 0.583; 95% CI, 0.360-0.942). Conclusions: Although assault prevention is not the sole reason for ordering IM medications, IM medication order rates are high relative to overall assault incident risk. Of the 3 major categories of medications ordered commonly in the psychiatric emergency setting, only antipsychotic medications were associated with measurable decreases in subsequent assault risk. As antipsychotic medication can have a significant side effect burden, careful weighing of the risks and benefits of medications is encouraged.