Estimating the Prevalence of Acute Agitation Associated with Schizophrenia and Bipolar Disorder

While acute agitation associated with psychiatric illness is common in U.S. emergency departments (ED), its prevalence in these settings is poorly characterized. Therefore, a study estimated the prevalence of agitation associated with schizophrenia or bipolar disorder that contributes to these ED visits. The findings were presented as a poster at AMCP Nexus 2021.

Researchers conducted a systematic literature review of Medline, Embase, and PsychInfo between January 2000 to 2021 to identify data on the prevalence of adults diagnosed with schizophrenia or bipolar disorder. The search yielded an estimate based on published administrative claims data from California Medicaid, privately insured, and dually eligible Medicaid/Medicare adults diagnosed with schizophrenia between 1999 through 2003. Bipolar disorder was defined as bipolar disorder I, bipolar disorder II, or subthreshold bipolar disorder.

The investigators used symphony claims data from 2017 through 2020 to estimate the percentage of adult patients with schizophrenia or bipolar disorder presenting with agitation. Patients with agitation were defined as those with at least one diagnostic code for any type of agitation along with a diagnosis or prescription claim during 12 months before and after the index date.

The analysis found that the prevalence of patients presenting to U.S. EDs with acute agitation associated with schizophrenia or bipolar disorder was approximately 325,000 for schizophrenia and 1.2 million for bipolar disorder. “There are limited data regarding national prevalence of hospital ED visits by patients with agitation associated with schizophrenia or bipolar disorder,” the researchers concluded.

“Analysis of data from multiple sources, suggests that episodes of agitation associated with schizophrenia or bipolar disorder are prevalent in U.S. emergency settings. Due to coding variability, available data may underestimate the actual prevalence.”

Source: Palko L, Inocencio T, Hokett S. Estimating the Prevalence of Acute Agitation Associated with Schizophrenia and Bipolar Disorder Resulting in Emergency Department Visits in the U.S. Poster F17.Published for AMCP Nexus 2021; Oct. 18-21, 2021, Denver, CO.