Association of the Affordable Care Act Medicaid Expansion with Trauma Outcomes and Access to Rehabilitation among Young Adults: Findings Overall, by Race and Ethnicity, and Community Income Level

BACKGROUND: Low-income young adults disproportionately experience traumatic injury and poor trauma outcomes. This study aimed to evaluate the effects of the Affordable Care Act’s Medicaid expansion, in its first 4 years, on trauma care and outcomes in young adults, overall and by race, ethnicity, and ZIP code-level median income. STUDY DESIGN: Statewide hospital discharge data from 5 states that did and 5 states that did not implement Medicaid expansion were used to perform difference-in-difference (DD) analyses. Changes in insurance coverage and outcomes from before (2011–2013) to after (2014–2017) Medicaid expansion and open enrollment were examined in trauma patients aged 19 to 44 years. RESULTS: Medicaid expansion was associated with a decrease in the percentage of uninsured patients (DD −16.5 percentage points; 95% CI, −17.1 to −15.9 percentage points). This decrease was larger among Black patients but smaller among Hispanic patients than White patients. It was also larger among patients from lower-income ZIP codes (p < 0.05 for all). Medicaid expansion was associated with an increase in discharge to inpatient rehabilitation (DD 0.6 percentage points; 95% CI, 0.2 to 0.9 percentage points). This increase was larger among patients from the lowest-compared with highest-income ZIP codes (p < 0.05). Medicaid expansion was not associated with changes in in-hospital mortality or readmission or return ED visit rates overall, but was associated with decreased in-hospital mortality among Black patients (DD −0.4 percentage points; 95% CI, −0.8 to −0.1 percentage points). CONCLUSIONS: The Affordable Care Act Medicaid expansion, in its first 4 years, increased insurance coverage and access to rehabilitation among young adult trauma patients. It also reduced the socioeconomic disparity in inpatient rehabilitation access and the disparity in in-hospital mortality between Black and White patients.