Real-World Evidence of Antipsychotic Monotherapy Versus Polypharmacy in the Treatment of Schizophrenia Spectrum Disorders

Purpose/BackgroundIt is still not well known whether antipsychotic monotherapy versus polypharmacy differs in terms of efficacy in the emergency department (ED) utilization, presentation with agitation/aggression, and rehospitalization in schizophrenia spectrum disorders (SSD) patients. This study aimed to determine the effectiveness of antipsychotic monotherapy and polypharmacy for these outcomes in the real world.Methods/ProceduresThe study was conducted with electronic health records of 669 SSD patients admitted to the ED. Patients were evaluated in 4 groups according to antipsychotic use at the first admission to ED: antipsychotic noncompliance for more than 90 days, antipsychotic noncompliance for 15 to 90 days, antipsychotic monotherapy, and polypharmacy. All patients followed up for at least 1 year after index admission. The primary outcomes determined an association between antipsychotic monotherapy versus polypharmacy and all-cause psychiatric hospitalization between the groups after index admission in the SSD.Findings/ResultsThe groups, including patients with antipsychotic noncompliance, had higher ED visits, more hospitalizations, and more admissions with agitation/aggression compared with antipsychotic monotherapy or polypharmacy. However, no differences were found between monotherapy and polypharmacy groups regarding these outcomes. In addition, there was no difference in the risk of hospitalization in monotherapy antipsychotic users compared with polypharmacy users. Patients discharged with monotherapy or polypharmacy also had similar rehospitalization rates at follow-up.Implications/ConclusionsThere is no positive evidence that recommending polypharmacy over antipsychotic monotherapy is superior with regard to the resulting frequency of ED visits, ED admissions with agitation/aggression, hospitalization, and rehospitalization. In this context, antipsychotic monotherapy may be preferred over polypharmacy in patients who are not resistant to treatment.