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Member Research & Reports

Member Research & Reports

Yale: Household Immigration Status May Impact Medicaid Enrollment

Individuals who are eligible for Medicaid and living in households with undocumented immigrants appear less likely to enroll in the public health insurance program in some states, a new study by the Yale School of Public Health finds.

Published in the March issue of Health Affairs, the study shines light on why approximately one in four of the uninsured in the United States was eligible for, but not enrolled in, the Medicaid program in 2016 — two years after expansions of Medicaid eligibility under the Affordable Care Act (ACA). The researchers used 2009 – 2015 data from the U.S. Census Bureau to identify Medicaid-eligible individuals in households that likely included at least one undocumented immigrant and examined trends in Medicaid coverage over time.

The researchers found that in states that expanded Medicaid eligibility, the rate of Medicaid enrollment was statistically indistinguishable between Medicaid-eligible individuals living in households with mixed-immigration status — with at least one likely undocumented immigrant — and those in households with non-mixed-immigration status. Medicaid enrollment increased commensurately in both populations following implementation of Medicaid expansion.

However, in non-expansion states, Medicaid enrollment was lower for eligible individuals living in mixed-status households. While Medicaid enrollment increased for individuals in non-mixed-status households in these states, similar increases in enrollment were not evident among individuals in mixed-status households, the researchers said.

“Our findings suggest that living in a mixed-status household may have dampened the so-called ‘woodwork effect,’ in which the ACA improved knowledge about Medicaid availability and increased enrollment in the program, even in non-expansion states,” said Mr. Michael Cohen, a PhD candidate in health policy and management and a study co-author.

Evidence of reduced Medicaid enrollment among eligible individuals in mixed-status households could be partially attributed to fear in some states that applying for public benefits may expose household members to scrutiny from immigration law enforcement agencies, the researchers noted. Other studies have shown that immigration enforcement activities reduced Medicaid enrollment among eligible children of non-citizens.

“Our findings may also suggest that certain states are particularly effective at making relevant enrollment information available and at helping eligible individuals enroll in the Medicaid program,” said William Schpero, a PhD candidate in health policy and management and the study’s co-author. “It is possible that differences across states in immigration enforcement or in information availability may underlie our results.”

States can improve Medicaid enrollment among eligible individuals in mixed-status households by explicitly clarifying that insurance application information will not be shared with immigration law enforcement agencies, the authors suggest. Increased availability of bilingual enrollment materials and assisters, as well as outreach to trusted community organizations, may also increase Medicaid enrollment within this eligible sub-population, they add.

The study was supported by funding from the Agency for Healthcare Research and Quality and the National Institute on Aging.