Overall, the authors estimated 10 additional ED visits per 1,000 people. As predicted, Medicaid expansion resulted in more visits by patients with Medicaid. The proportion of visits covered by Medicaid increased from 35 percent pre-ACA to 48 percent during the study. The authors argue that some of this increase may be temporarily caused by pent-up demand from patients who needed health care but could not afford it prior to the ACA. A reciprocal decrease in the proportion of uninsured visits was noted (from 23 percent down to 11 percent).

Further analyzing the data provides interesting insights into the chief complaints that became more common for patients with Medicaid. The largest increases were for dental and mental health visits, which aligns with the disproportionate number of Medicaid-eligible patients who report less than excellent mental health.¹⁰

Naturally, increased visits raise questions about the effects on emergency departments. Without an increase in capacity, more visits may mean overcrowding, decreased quality of care, and worse patient outcomes. Changes in payer mix affect the hospital’s bottom line, since Medicaid generally reimburses less than private insurance. However, Medicaid reimbursement is higher than that from self-pay patients. Furthermore, recognizing that there are fewer uninsured patients, the ACA reduces payments for hospitals serving a disproportionately high level of uninsured patients.¹¹ The balance of these clinical and financial forces should continue to be explored.

Dr. Dark is assistant professor of emergency medicine at Baylor College of Medicine in Houston and executive editor of Policy Prescriptions.

Dr. Maughan is an emergency medicine resident at Maine Medical Center in Portland, Maine.

Dr. Sontag is an emergency medicine resident at UT Health San Antonio.

References

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2. ACEP. ER visits continue to rise since implementation of Affordable Care Act. ACEP website. Accessed March 23, 2018.
3. Dresden SM, Powell ES, Kang R, et al. Increased emergency department use in Illinois after implementation of the Patient Protection and Affordable Care Act. Ann Emerg Med. 2017;69(2):172-180.
4. Taubman SL, Allen HL, Wright BJ, et al. Medicaid increases emergency-department use: evidence from Oregon’s health insurance experiment. Science. 2014;343(6168):263-268.
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10. Newport F. Strong relationship between income and mental health. Gallup web site. Accessed March 23, 2018.
11. Medicaid and CHIP Payment and Access Commission. Report to Congress on Medicaid disproportionate share hospital payments. MACPAC website. Accessed March 23, 2018.