The Effect of Medicaid Expansion on the Nature of New Enrollees’ Emergency Department Use

Abstract

We examine changes in emergency department (ED) visit acuity and care intensity for uninsured patients who gained Medicaid insurance in 2014 under the Patient Protection and Affordable Care Act. We use 2013-2015 longitudinal patient visit-level data from 30 EDs across 7 states from an emergency medicine group. We examine changes in ED use by previously uninsured Medicaid patients and patients remaining uninsured who were repeat ED users (≥1 visit before and after expansion) using a propensity-score weighted approach with statistical machine learning to estimate the weights. Compared with those remaining uninsured in nonexpansion states, newly covered Medicaid patients in expansion states showed a 29% relative increase in hospital admissions and 32% increase in admissions for nonambulatory care sensitive conditions with no increases in care intensity. Obtaining Medicaid insurance increased the relative proportion of ED visits requiring hospital admission suggesting increased outpatient access for low-acuity conditions previously addressed with ED care.

Hospital Utilization for Non-Traumatic Dental Conditions in Oregon from 2013 to 2015

“…This is a direct result of Medicaid expansion enrollment, as similar patterns were observed in only Medicaid-enrolled patients with 9,798 total visits in 2013 and 21,758 in 2015. Inpatient and emergency department utilization peaked in 2014, both for those with all insurances and Medicaid-only; this finding is consistent with the literature demonstrating similar increases in 2014 with Medicaid expansion, and resulting declines in ED utilization beginning in 2015 (23).…”

“…Additionally, inpatient admissions increased over the same time period as ED visits in our cohort. These findings correlate to previous studies looking at medically related increases in inpatient admissions after adult Medicaid expansion in Oregon and Connecticut (23)(24). Consistent with prior research, females are more likely than males to utilize the ED for dental related issues, particularly among those carrying Medicaid coverage (25)(26)(27).…”

“…Oregon experienced higher utilization in both the ED and the inpatient admissions for non-traumatic dental care at the outset of their Medicaid program. Previous analyses show that when adults gain coverage from public insurance programs there is an increase in utilization of all services, including EDs and that this trend continues for newly enrolled recipients for at least two years after enrollment (22)(23). Additionally, inpatient admissions increased over the same time period as ED visits in our cohort.…”

Hospital Utilization for Non-Traumatic Dental Conditions in Oregon from 2013 to 2015

“…This is a direct result of Medicaid expansion enrollment, as similar patterns were observed in only Medicaid-6 enrolled patients with 9,798 total visits in 2013 and 21,758 visits in 2015. Inpatient and emergency department utilization peaked in 2014, both for those with all insurances and Medicaid-only; this finding is consistent with the literature demonstrating similar increases in 2014 with Medicaid expansion, and resulting declines in ED utilization beginning in 2015 (23).…”

“…Oregon experienced higher utilization in both the ED and the inpatient admissions for NTDC at the outset of their Medicaid program. Previous analyses show that when adults gain coverage from public insurance programs there is an increase in utilization of all services, including emergency departments and that this trend continues for newly enrolled recipients for at least two years after enrollment (22)(23). Additionally, inpatient admissions increased over the same time period as ED visits in our cohort.…”