A new study published in the October 2023 edition of Health Affairs shows that Medicaid expansion has the greatest impact on lowering uninsurance rates among nonelderly adults in metropolitan communities with the highest levels of historical residential redlining. The study was led by Jason Semprini, postdoctoral scholar in the Department of Epidemiology at the University of Iowa College of Public Health.

The researchers found that states that expanded Medicaid in accordance with the Affordable Care Act (ACA) saw an average decrease of 6.2 percentage points in the number of people who were uninsured in the most heavily redlined census tracts.

“These findings add to the evidence that structural racism, not race, is the cause of racial and ethnic health insurance disparities,” says Semprini. “To truly advance health equity, policymakers must address the dire effects of structural racism on health by prioritizing and incentivizing financial, educational, and health sector investments in these historically redlined communities.”

For non-expansion states, average uninsurance rates in areas with the highest level of redlining were 15.7 percent for non-Hispanic Black, 13.6 percent for non-Hispanic White, and 23.4 percent for Hispanic nonelderly adults.

The publication was co-authored by Abdinasir K. Ali from the University of Iowa and Gabriel A. Benavidez from the University of South Carolina.

Read a story about this research from the Des Moines Register: How Medicaid expansion has helped redlined neighborhoods in Iowa, across US, get insured