Epidemiology and characteristics of emergency departments visits by US adults with psychiatric disorder and antipsychotic mention from 2000 to 2004.

BACKGROUND AND OBJECTIVE: There is limited research to acquaint clinicians and payers about antipsychotic use in psychiatric patients visiting United States (US) emergency departments (EDs). The study objective is to describe the epidemiology and compare characteristics of ED visits by adults > or = 18 years with psychiatric diagnoses and different types of antipsychotic.

METHODS: Data for 2000-2004 adult ED visits were obtained from the National Hospital Ambulatory Medical Care Survey. Sample-weighted national estimates of (1) typical, (2) atypical, or (3) typical-atypical combination antipsychotic-associated psychiatric ED visits with 95% confidence intervals (CIs) were produced. Characteristics of the three psychiatric ED visit groups with antipsychotic mention, (prescribed, supplied, administered, ordered or continued) were analyzed retrospectively. Significant characteristics for atypical versus typical antipsychotic mention at visits were determined using multivariate logistic regression.

RESULTS: Adults made an estimated 26 million ED visits over the 5-year study period that resulted in a psychiatric diagnosis. Of 2 million (or 8%) of these psychiatric ED visits, 38, 55, and 8% mentioned typical, atypical, and combination antipsychotics respectively. From 2000 to 2004 there was an 8-, 3.5-, and 1.5-fold increase in ED visits with combination, atypical, and typical antipsychotics, respectively. The majority of antipsychotic-associated psychiatric ED visits were made by young adults less than 40 years old, Caucasians, needing urgent treatment, and reimbursed by public insurance. More combination-, and typical versus atypical antipsychotic-associated ED visits included a mention of medications for extrapyramidal symptoms (40%, 14% vs. 4%; p < 0.0001) and antianxiety medications (50%, 48% vs. 27%; p < 0.0001). More combination and atypical than typical antipsychotic-related ED visits had anticonvulsant (42%, 35% vs. 12%; p < 0.0001) and antidepressant mentions (31%, 42% vs. 11%; p < 0.0001). A diagnosis of depression (OR 3.2, 95% CI: 1.9-5.3; p < 0.001) or bipolar-disorder (OR 2.5, 95% CI: 1.3-5.0; p = 0.008), and the number of medications received (OR 1.4, 95% CI: 1.0-1.8; p = 0.034) significantly increased the likelihood of atypical versus typical antipsychotic mention at psychiatric ED visits.

CONCLUSIONS: Despite limitations of analyses with cross-sectional visit data, an increasing number of combination- and atypical antipsychotic-associated US adult ED visits depict the burden on the healthcare system. The associated characteristics of these visits deserve the attention of providers, and payers for cost-effective patient management.