MODELING EMERGENCY DEPARTMENT UTILIZATION

Purpose: Although young adults are a generally healthy population, they account for a substantial proportion of emergency department (ED) visits and often lack health insurance. The 2010 Affordable Care Act (ACA) was designed to improve health care for all Americans and reduce disparities; it included a provision to allow young adults ages 19–25 to remain as dependents on their parents’ private insurance policies. This provision appears to have increased insurance coverage and reduced ED utilization among young adults. However, since it is contingent on parents’ insurance status, it may differentially benefit racial/ethnic groups.

Method: Using state administrative records that capture all ED visits and followed all ED users over time in five diverse states (California, Florida, Iowa, Massachusetts and New York), we identified the changes in ED utilization among adults aged 19-25 before and after the dependent coverage provision of the ACA. We compared the changes in ED use among this group to that of older adults aged 26-31 who were unaffected by the provision but were affected by simultaneous economic forces and health reforms unrelated to the dependent coverage provision, to filter out the effect of confounders. We used a zero-inflated model to test for discrepancies between the negative binomial model and the true data distribution.

Result: While the dependent coverage provision was associated with a significant decrease in the overall number of ED visits per patient (-1.2, p<.0001) and the probability that a young adult ever visited the ED (-0.8, p<.0001), the effect significantly differed by race/ethnic group. ED utilization primarily decreased among Whites (ProbVisit: -0.7, p<.0001) and Blacks (ProbVisit: -2.0, p<.05) and Hispanics had no significant change (ProbVisit: -0.1, p>.05).   

Conclusion:

The 2010 expansion of dependent coverage to young adults aged 19-25 was associated with overall reductions in ED utilization, but with significantly different effects by race/ethnic group. As EDs face capacity challenges, these results are encouraging and offer insight into what could be expected under further insurance expansions from health care reform.