We identify frequent users of the emergency department (ED) and determine the characteristics of these patients. Using the 2000 to 2001 population-based, nationally representative Community Tracking Study Household Survey, we determined the number of adults (aged 18 and older) making 1 to 7 or more ED visits and the number of visits for which they accounted. Based on the distribution of visits, we established a definition for frequent user of 4 or more visits. Multivariate analysis assessed the likelihood that individuals with specific characteristics used the ED more frequently. An estimated 45.2 million adults had 1 or more ED visits. Overall, 92% of adult users made 3 or fewer visits, accounting for 72% of all adult ED visits; the 8% of users with 4 or more visits were responsible for 28% of adult ED visits. Most frequent users had health insurance (84%) and a usual source of care (81%). Characteristics independently associated with frequent use included poor physical health (odds ratio [OR] 2.54; 95% confidence interval [CI] 2.08 to 3.10), poor mental health (OR 1.70; 95% CI 1.42 to 2.02), greater than or equal to 5 outpatient visits annually (OR 3.02; 95% CI 1.94 to 4.71), and family income below the poverty threshold (OR 2.36; 95% CI 1.70 to 3.28). Uninsured individuals were more likely to report frequent use, but this result was only marginally significant (OR 2.38; 95% CI 0.99 to 5.74). Individuals who lacked a usual source of care were actually less likely to be frequent users. The majority of adults who use the ED frequently have insurance and a usual source of care but are more likely than less frequent users to be in poor health and require medical attention. Additional support systems and better access to alternative sites of care would have the benefit of improving the health of these individuals and may help to reduce ED use.
