Insured Americans Drive Surge in Emergency Department Visits

Originally published by the Center for Studying Health System Change (HSC), a nonpartisan policy research organization that operated with principal funding from the Robert Wood Johnson Foundation.

Issue Brief No. 70 -- October 2003

Authors: Peter J. Cunningham, Jessica H. May

The Surge in Emergency Department Visits

Hospital emergency department (ED) visits had risen sharply in recent years, fueling overcrowded conditions and forcing ambulance diversions at hospitals across the country. Contrary to the widespread assumption that uninsured Americans were the primary driver of this increase, an HSC study found that insured patients -- particularly those with private coverage -- accounted for the majority of the 16 percent jump in ED visits between 1996-97 and 2000-01. The study examined trends in emergency department and broader ambulatory care utilization, with particular attention to how patterns differed across insurance categories.

Trends in Emergency Department Utilization

Data from the National Hospital Ambulatory Medical Care Survey showed an average of 108 million ED visits each year during 2000 and 2001, representing a 16 percent increase from the 1996-97 period. Three-quarters of this increase resulted from higher per-person utilization -- the average rose from 35 visits per 100 people in 1996-97 to 39 per 100 in 2000-01. The remaining quarter of the increase was attributable to overall population growth.

ED visits by privately insured individuals climbed 24 percent during this period, far outpacing the 4.7 percent growth in the privately insured population. Medicare beneficiaries' ED use grew by 10 percent, still above the 4.1 percent increase in Medicare enrollment. Together, privately insured and Medicare patients accounted for roughly two-thirds of the total increase in ED visits, with privately insured people alone responsible for more than half. Medicaid beneficiaries' ED visits held steady despite a 10 percent increase in program enrollment, while visits by uninsured patients rose about 10 percent despite little change in the uninsured population -- meaning the uninsured accounted for only 11 percent of the overall increase.

How Ambulatory Care Patterns Differed by Insurance Status

For privately insured people, the 24 percent rise in ED visits tracked with a broader increase in all types of ambulatory care -- physician office visits rose 29 percent and hospital outpatient department visits grew 31 percent during the same period. Because ambulatory care use climbed across the board, ED visits as a share of all ambulatory visits for the privately insured stayed at roughly 8 percent. Medicare beneficiaries followed a similar pattern, though the changes were smaller in scale.

For Medicaid enrollees, the picture was different. Their flat ED utilization came alongside an 8 percent drop in hospital outpatient visits and a 12.5 percent decline in physician office visits. As a result, ED visits as a proportion of all ambulatory care for Medicaid beneficiaries reached 17.5 percent by 2000-01 -- more than double the rate for privately insured and Medicare patients.

The most striking shift occurred among uninsured patients. Physician office visits for the uninsured plummeted 37 percent between 1996-97 and 2000-01, while hospital outpatient visits changed little. Combined with the increase in ED use, uninsured Americans had come to rely on emergency departments for a full quarter of their ambulatory care visits -- up from 17 percent just a few years earlier. This growing dependence on EDs reflected declining access to office-based physicians, as fewer doctors were providing charity care and fewer uninsured individuals reported having a regular source of care outside the emergency department.

Urgency Levels and the Question of Nonurgent ED Visits

Analysis of ED visit triage data from 1999-2000 showed that 47 percent of all visits were classified as emergent or urgent, while about 27 percent were categorized as semi-urgent or nonurgent, and the remainder had unknown triage status. Across insurance categories, privately insured patients had semi-urgent or nonurgent visits at rates similar to the overall average (26.5 percent). Medicare beneficiaries had the highest share of emergent or urgent visits (56.9 percent), while Medicaid and uninsured patients had higher rates of semi-urgent or nonurgent visits (30.8 percent and 31.3 percent, respectively).

Waiting Times and Perceptions of Care Quality

Emergency department waiting times increased substantially during the study period, and longer waits were associated with lower perceptions of care quality among patients. The crowding that resulted from higher visit volumes made it harder for emergency departments to see patients promptly, creating a cycle in which overcrowding degraded the patient experience even for those with genuinely urgent medical needs.

Policy Implications

The findings challenged the common narrative that emergency department crowding was primarily a problem of uninsured patients seeking care they could not get elsewhere. While the uninsured were indeed becoming more dependent on EDs, the sheer volume of the increase was driven by insured Americans using more health care of all types, including emergency services. For public hospitals and safety net institutions serving large numbers of uninsured patients, however, the rising share of ambulatory care delivered through the ED raised serious concerns about capacity, cost, and the ability to provide timely care to those most in need.

Sources and Further Reading

AHRQ -- Federal health care quality research agency.

National Center for Health Statistics -- Source of National Hospital Ambulatory Medical Care Survey data.

Health Affairs -- Peer-reviewed health policy research.

Robert Wood Johnson Foundation -- Health policy research and funding.