Epidemiology of adult psychiatric visits to US emergency departments.

OBJECTIVES To characterize psychiatric-related emergency department visits (PREDVs) among adults in the United States for the year 2000 and to analyze PREDV trends from 1992 to 2000. METHODS Emergency department (ED) visit data from the National Hospital Ambulatory Medical Care Survey were used to estimate the number of PREDVs for adults aged 18 years and older. A PREDV was defined as any visit with a psychiatric discharge diagnosis (ICD N290- N312) or a suicide attempt (ICD E950-E959). RESULTS Approximately 4.3 million PREDVs occurred in the United States in the year 2000, yielding an annual rate of 21 visits per 1000 adults. The PREDV rates increased 15% between 1992 and 2000. The PREDVs accounted for 5.4% of all ED visits. Substance abuse (27%), neuroses (26%), and psychoses (21%) were the most common conditions. African Americans had significantly higher visit rates (29/1000; 95% CI = 27/1000 to 31/1000) compared with whites (23/1000; 95% CI = 22/1000 to 25/1000). Persons with Medicaid (66/1000; 95% CI = 64/1000 to 68/1000) had double the rate of PREDVs than the uninsured (33/1000; 95% CI = 31/1000 to 35/1000) and almost eight times the rate of those privately insured (8/1000; 95% CI = 7/1000 to 10/1000). Patients with psychiatric diagnoses had a higher admission rate (22%) than those with nonpsychiatric diagnoses (15%). The uninsured were the least likely to be admitted for all major psychiatric conditions except suicide (p < 0.0001). CONCLUSIONS Psychiatric-related ED visits represent a substantial and growing number of ED visits each year. Patient characteristics influence the likelihood of a PREDV. Further research is needed to better understand the role that hospital EDs play in the delivery of health care services to those with mental illness.