SAN FRANCISCO — Most adults seen in emergency departments have health insurance and a usual source of care, countering the common notion that uninsured patients are using emergency departments because they have nowhere else to go, Ellen J. Weber, M.D., said at the annual meeting of the American College of Emergency Physicians.
She and her associates extrapolated from data on a population-based sample of 49,603 adults to estimate that more than 45 million U.S. adults made nearly 80 million visits to EDs over a 1-year period. Of those who went to emergency departments, 83% said they had a usual source of care other than the ED (accounting for 82% of ED visits), and 85% had some form of health insurance (accounting for 85% of ED visits), said Dr. Weber.
Improving the delivery of outpatient care may be the key to decreasing ED use, the investigators concluded.
The study is one of a few that compare ED users with nonusers in these respects. The results showed that uninsured adults were no more likely to visit the ED during the study period than were people with private insurance. Compared with privately insured patients, those with Medicaid or Medicare were 51% and 19% more likely, respectively, to use the ED.
Adults with no usual source of care were 25% less likely to visit the ED than were adults whose usual care came from a private physician. Patients who used the ED for their usual care or who had no source of usual care were responsible for only 17% of ED visits.
People who used the ED most had poor health or changes in their usual care or insurance, the study found.
People with poor physical health were more than twice as likely to have visited an ED as were people in good health, and they accounted for nearly half of all ED visits. People with poor mental health were 51% more likely to go to an ED than were people with good mental health. People who had had a change in their usual source of care were 30% more likely to seek help in an ED than were people with stable care. A change in insurance increased the odds of an ED visit by 15%.
Poverty increased the likelihood of an ED visit, but patients with incomes below the poverty level accounted for only one in five visits.
“People affected by ED overcrowding and closures of emergency departments are the seriously ill,” said Dr. Weber, medical director of the emergency department at the University of California, San Francisco.
Data for the study came from the Community Tracking Study Household Survey. The Center for Studying Health System Change, a nonpartisan policy research group in Washington, conducted the survey. The survey data, from July 2000 through June 2001, included interviews in English or Spanish with up to eight adults per household in 60 communities and in a national sample, plus administration of the SF-12 Health Survey.
Several factors thought to decrease ED usage were not associated with fewer visits, including enrollment in an HMO, early availability of appointments, and patients' satisfaction with their primary physicians.
Previous studies reported conflicting data about whether people visiting EDs were more likely to be uninsured or to have no usual source of care, perhaps because they studied individual departments, focused on special populations, and didn't compare ED visitors to nonvisitors, Dr. Weber said.
KEVIN FOLEY, RESEARCH/DESIGN