UAlbany Study Finds Medicaid Expansion Boosted Coverage for Indigenous Communities
ALBANY, N.Y. (June 18, 2026) — American Indian and Alaska Native populations continue to experience higher rates of uninsurance and chronic disease than many other groups in the United States. Now, new research led by the University at Albany examines how different provisions of the Affordable Care Act affected insurance coverage among American Indian and Alaska Native people between 2011 and 2019.
The study, “Effects of National Insurance Reforms and State Medicaid Expansions Under the Affordable Care Act on Insurance Coverage Among American Indian and Alaska Native People,” was recently published in Health Services Research.
Authors Kate Strully, Pinka Chatterji and Han Liu found that Medicaid expansion played a far greater role in increasing insurance coverage than the ACA's national insurance marketplace reforms, highlighting the importance of state-level policy decisions around Medicaid in reducing coverage disparities.
Coverage gains tied to state decisions
The study analyzed insurance outcomes for more than 12 million Americans from multiple racial-ethnic groups and compared the effects of state Medicaid expansions with the ACA's national insurance reforms.
Among the key findings:
- Medicaid expansion enacted by states reduced uninsurance among American Indian and Alaska Native respondents by approximately 9 percentage points.
- Increases in coverage were especially pronounced among respondents who reported access to the Indian Health Service in addition to Medicaid. National ACA reforms, including insurance marketplaces and subsidies, did not have statistically detectable effects on insurance outcomes for American Indian and Alaska Native populations.
“Our findings show that Medicaid expansion was the primary driver of insurance gains for American Indian and Alaska Native populations during this period,” said Strully, associate professor of sociology at UAlbany. “The results add to a growing body of evidence documenting the key role of Medicaid in reducing insurance disparities and the importance of states protecting Medicaid in this time of unprecedented cuts.”
The researchers note that Medicaid serves an important role beyond individual coverage by helping support Tribal and Indian Health Service health systems through reimbursement funding.
Effects across racial and ethnic groups
The study also found that ACA policies did not affect all populations equally. Black respondents experienced insurance gains from both Medicaid expansion and national ACA reforms, while White respondents, who had higher rates of insurance coverage prior to the ACA, saw smaller overall improvements in coverage. Hispanic respondents, similar to American Indian and Alaska Native populations, benefited more from Medicaid expansion than from national marketplace reforms.
“One of the strengths of this research is that it allows us to separate the effects of different ACA policies rather than treating the law as a single intervention,” said Chatterji, professor of economics at UAlbany and co-author of the study. “Understanding which policy tools were most effective can help inform future efforts to reduce disparities in insurance coverage and access to care.”
“These findings show why it is important to look closely at how different parts of a major policy work for different populations,” said Liu, an bridge-to-faculty postdoctoral fellow at the University of Texas at San Antonio who received his PhD in sociology from UAlbany in 2023.
The paper follows related research published in Health Affairs in 2024 by Chatterji, Strully, Liu, Soojin Han, a UAlbany PhD student, and Lawrence Schell, a Distinguished Professor in the departments of Anthropology and Epidemiology & Biostatistics.
That study found that Medicaid expansion increased health care coverage among American Indian and Alaska Native women and documented that American Indian and Alaska Native women are overrepresented in counties facing health care shortages, particularly a lack of physicians and specialists.
Both studies were supported through a research grant from the National Institutes of Health.