Annals of Emergency Medicine
Volume 52, Issue 2 , Pages 108-115.e1, August 2008

Are the Uninsured Responsible for the Increase in Emergency Department Visits in the United States?

Presented as an abstract at the Fourth Mediterranean Emergency Medicine Conference, September 2007, Sorrento, Italy.

  • Ellen J. Weber, MD

      Affiliations

    • Division of Emergency Medicine, School of Medicine, University of California, San Francisco, San Francisco, CA
    • Corresponding Author InformationAddress for correspondence: Ellen J. Weber, MD, Emergency Department, Box 0208, University of California, San Francisco, San Francisco, CA 94143-0208; 415-353-1109, fax 415-353-1799
  • ,
  • Jonathan A. Showstack, PhD, MPH

      Affiliations

    • Institute for Health Policy Studies, School of Medicine, University of California, San Francisco, San Francisco, CA
  • ,
  • Kelly A. Hunt, MPP

      Affiliations

    • New York State Health Foundation, New York, NY
  • ,
  • David C. Colby, PhD

      Affiliations

    • Robert Wood Johnson Foundation, Princeton, NJ.
  • ,
  • Barbara Grimes, PhD

      Affiliations

    • Department of Epidemiology and BiostatisticsSchool of Medicine, University of California, San Francisco, San Francisco, CA
  • ,
  • Peter Bacchetti, PhD

      Affiliations

    • Department of Epidemiology and BiostatisticsSchool of Medicine, University of California, San Francisco, San Francisco, CA
  • ,
  • Michael L. Callaham, MD

      Affiliations

    • Division of Emergency Medicine, School of Medicine, University of California, San Francisco, San Francisco, CA

Received 1 October 2007; received in revised form 1 December 2007 and 4 January 2008; accepted 23 January 2008. published online 14 April 2008.

Study objective

The rise in emergency department (ED) use in the United States is frequently attributed to increased visits by the uninsured. We determine whether insurance status is associated with the increase in ED visits.

Methods

Using the national Community Tracking Study Household Surveys from 1996 to 1997, 1998 to 1999, 2000 to 2001, and 2003 to 2004, we determined for each period the proportion of reported adult ED visits according to insurance status, family income, usual source of care, health status, and outpatient (non-ED) visits. Trends over time were tested for statistical significance.

Results

The proportion of adult ED visits by persons without insurance was stable across the decade. Uninsured individuals accounted for 15.5% of ED visits in 1996 to 1997, 16.1% in 1998 to 1999, 15.2% in 2000 to 2001, and 14.5% of visits in 2003 to 2004 (P for trend=.43). The proportion of visits by persons whose family income was greater than 400% of the federal poverty level increased from 21.9% to 29.0% (P=.002). The proportion of visits by those whose usual source of care was a physician's office increased from 52.4% in 1996 to 1997 to 59.0% in 2003 to 2004 (P=.002), whereas the proportion of visits by those without a usual source of care was essentially unchanged (9.7% of visits in 1996 to 1997 and 9.6% in 2003 to 2004; P=.74).

Conclusion

The rise in ED visits between 1996 and 2003 cannot be primarily attributed to the uninsured. Major contributors to increasing ED utilization appear to be disproportionate increases in use by nonpoor persons and by persons whose usual source of care is a physician's office.

 

 Supervising editor: Donald M. Yealy, MD

 Funding and support: By Annals policy, all authors are required to disclose any and all commercial, financial, and other relationships in any way related to the subject of this article, that might create any potential conflict of interest. See the Manuscript Submission Agreement in this issue for examples of specific conflicts covered by this statement. Statistical analysis was supported by an intramural grant from UCSF's Academic Senate.

 Author contributions: EJW, JAS, KAH, DCC, and MLC conceived the study, determined the theoretical model, and interpreted the results. EJW, JAS, and KAH designed the analyses. JAS, KAH, BG, and PB provided statistical consultation. KAH and BG programmed the data. EJW drafted the article, with contributions from all authors. All authors contributed substantially to revisions of the draft article. EJW takes responsibility for the paper as a whole.

 Dr. Callaham has recused himself from the editorial review of this article.

 Publication dates: Available online April 14, 2008.

 Reprints not available from the authors.

PII: S0196-0644(08)00365-X

doi:10.1016/j.annemergmed.2008.01.327

Annals of Emergency Medicine
Volume 52, Issue 2 , Pages 108-115.e1, August 2008