Medicaid Expansion and Emergency Room Usage: A Comparison of Expansion and Non-Expansion States

Objectives: The objective of the study was to determine whether Medicaid expansion caused a rise in ER visits in two states that elected to expand coverage (Arkansas and Kentucky). We compared the ER visits in two states that did not choose to expand Medicaid coverage (South Carolina and Georgia). Methods: The study uses a quasi-experimental design to examine changes in ED utilization in Kentucky and Arkansas as a result of Medicaid expansion. These utilization rates were compared with utilization data from Georgia and South Carolina. Results: Monthly ED visit (resulting in discharges) volume by adults aged 18-64 in expansion states increased in the post expansion period at a higher rate than the non-expansion states. Medicaid ED visits in expansion states increased in the post expansion period at a higher rate than the non-expansion states. Self- pay ED visits in expansion states decreased in the post expansion period at a higher rate than the non-expansion states. Discussion: Increase in total ED visit volume runs contrary to one of the key intents of health insurance expansion to reduce higher cost services such as ED visits. Previously uninsured patients that transitioned to Medicaid in expansion states are now using the ED more frequently. Medicaid expansion did not reduce the burden on existing EDs. The volumes have gone up across the board and only the insurance status (self-pay to Medicaid) has changed in those states