FRIDAY, March 30 (HealthDay News) -- People who have experienced recent changes in their health insurance status are more likely to use hospital emergency departments, a new study finds.

The use of emergency departments is an important indicator of access to care. People who have difficulty obtaining outpatient care often turn to emergency departments for medical care, said Dr. Adit Ginde, of the University of Colorado School of Medicine, and colleagues.

The researchers analyzed data from nearly 160,000 adults who took part in the 2004 to 2009 National Health Interview Study, and found that 21 percent of insured adults and 20 percent of uninsured adults had made at least one visit to an emergency department during the previous year.

Further analysis of the data revealed that nearly 30 percent of newly insured adults (those who were insured but lacked insurance at some point during the previous year) had at least one emergency department visit, compared with 20 percent of continuously insured adults.

The researchers also found that 26 percent of newly uninsured adults (those who were uninsured but had insurance at some point in the previous year) had at least one emergency department visit, compared with 19 percent of continuously uninsured adults.

"In conclusion, although adjusted [emergency department] use rates were similar for insured adults and uninsured adults, those with recent changes in health insurance status had greater [emergency department] use," the researchers wrote. "Adults with new Medicaid coverage were disproportionately likely to use [emergency departments], suggesting that their reduced out-of-pocket cost for care was not associated with increased access to primary-care services."

The study was published in the March 26 online edition of the Archives of Internal Medicine as part of the journal's Health Care Reform series.

The Obama administration's health-care reform law is expected to result in 94 percent of the U.S. population having health insurance coverage by 2019, the researchers noted.

"Because health policy changes and economic forces are expected to create disruptions in health insurance status, policy makers and health care administrators should anticipate new surges in [emergency department] use," they concluded. "Consistency in provision and health insurance type may improve access to primary-care services and reduce patient reliance on [emergency department] services."

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