New research finds that socioeconomically disadvantaged groups may still be underusing emergency departments for potentially serious illnesses in the wake of the COVID pandemic, despite an overall rebound in emergency department use by 2022.
The UCLA-led study, in the peer-reviewed journal Health Affairs, shows that most of the rebound was driven primarily by patients covered by commercial insurance or Medicare fee-for-service. When stratified by insurance type, the rebound was found to be significantly lower among patients covered by Medicaid or dual Medicare/Medicaid, who tend to be socioeconomically disadvantaged.
The findings surprised the researchers, who expected socioeconomically disadvantaged patients to utilize the ED more compared to patients with more resources. Instead, less well-resourced patients exhibited lower relative utilization for non-avoidable visits, which raises concern that these groups are forgoing potentially life-saving care. This represents a reversal in the pre-pandemic trend of Medicaid and dual-eligible patients exhibiting increasing emergency department utilization compared to other insured groups.
“Our findings highlight a mixed reality: while fewer potentially avoidable ED visits suggest more efficient healthcare use, the concerning trend is that Medicaid and dual-eligible patients—who are often socioeconomically disadvantaged—may be forgoing necessary high-acuity care,” said Dr. Richard Leuchter, assistant professor of medicine at the and the study’s lead author. “This disparity, exposed by the COVID-19 pandemic, underscores yet another vulnerability in the U.S. healthcare system.”
The researchers analyzed data for 15.6 million ED visits from public and private insurance companies using the Milliman MedInsight Emerging Experience Research Database from the 50 U.S. states and Washington D.C. They used what is called the difference-in-differences method, which accounts for changes in outcomes over time for different groups, to compare ED use between March 2020 and August 2022 with rates from the same months in 2018-19.
They found that potentially avoidable visits declined by 25% for all insured groups early in the pandemic compared to the pre-pandemic period. Non-avoidable visits, which had declined by an overall 30%, rebounded to about 95 percent of expected rates by the end of the pandemic across all insured groups. But this rebound did not occur among Medicaid and dual-eligible patients, where utilization generally remained at 75% of expected rates by the end of the study period.
The researchers suspect that vulnerable groups may have been more likely to self-isolate early in the pandemic due to factors such as living in multi-generational households or fear of becoming infected with COVID, or later on prioritized work over seeking healthcare.
“To the best of our knowledge, this was the first nationwide study to report a persistent reversal in the pre-pandemic trend of increasing ED use by Medicaid and dual-eligible patients, which has important postpandemic policy implications,” the researchers write.
For instance, the findings should spur research into whether these trends persisted past the pandemic and examine how they may impact long-term health. In addition, the findings may have an effect on efforts to curb avoidable ED usage, such as having the unintended effect of reducing non-avoidable ED visits by Medicaid and dual-eligible patients.
There are limitations to the study. Among them, the analysis did not account for any changes in the patient mix in what was assumed to be a stable and homogenous patient cohort, nor did it account for individual patient characteristics, and it did not include uninsured patients or stratify ED visits by diagnosis. In addition, Medicaid or dual-eligibility are imperfect substitutes for determining socioeconomic status.
Though the research suggests a welcome reduction of emergency department utilization for non-emergency treatment, “it also indicates the emergence of a disparity whereby socioeconomically disadvantaged groups may be underusing the ED for higher-acuity illness,” the researchers conclude.
Study co-authors are Sitaram Vangala, Chi-Hong Tseng, Julia Cave Arbanas, Cyrus Tabatabai-Yazdi, Dr. Catherine Sarkisian, Dr. John Mafi and Dr. Katherine Kahn of UCLA, Cheryl Damberg of RAND Corporation, and Melody Craff, Michael Hadfield and Dale Skinner of Milliman MedInsight.
This study received funding from NHLBI (Grant No. 1K38 HL164955-01) and NIA (Grants Nos. 5K24AG047899-05, P30AG021684-16, and 1K76AG064392-01A1).
