Impact of Expanded Medicaid Eligibility on the Diabetes Continuum of Care Among Low-Income Adults: A Difference-in-Differences Analysis

  • Lily D. Yan
    Address correspondence to: Lily D. Yan, MD, MSc, Department of Internal Medicine, Center for Global Health, Weill Cornell Medicine, 402 East 67th Street, 2nd Floor, New York, NY 10065.
    Department of Internal Medicine, Boston Medical Center, Boston, Massachusetts

    Health Law, Policy and Management, Boston University School of Public Health, Boston, Massachusetts
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  • Mohammed K. Ali
    Hubert Department of Global Health, Emory University Rollins School of Public Health, Atlanta, Georgia

    Department of Family and Preventive Medicine, Emory University School of Medicine, Atlanta, Georgia
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  • Kiersten L. Strombotne
    Health Law, Policy and Management, Boston University School of Public Health, Boston, Massachusetts
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Published:November 11, 2020DOI:


      The impact of Medicaid expansion on linkage to care, self-maintenance, and treatment among low-income adults with diabetes was examined.


      A difference-in-differences design was used on data from the Behavioral Risk Factor Surveillance System, 2008–2018. Analysis was restricted to states with diabetes outcomes and nonpregnant adults aged 18–64 years who were Medicaid eligible on the basis of income. Separate analyses were performed for early postexpansion (1, 2, 3) and late postexpansion years (4, 5). Analyses were performed from September 2019 to March 2020.


      In comparing expansion with control states, low-income residents with diabetes had similar ages (48.9 vs 49.1 years) and similar proportions who were female (54.4% vs 55.0%) but were less likely to be Black, non-Hispanic (20.8% vs 29.2%, standardized difference= −16.3%). In expansion states, health insurance increased by 7.2 percentage points (95% CI=3.9, 10.4), and the ability to afford a physician increased by 5.5 percentage points (95% CI=1.9, 9.1) in the early years, but no difference was found in late years. Medicaid expansion led to a 5.3-percentage point increase in provider foot examinations in the early period (95% CI=0.14, 10.4) and a 7.2-percentage point increase in self-foot examinations in the late period (95% CI=1.1, 13.3). No statistically significant changes were detected in self-reported linkage to care, self-maintenance, or treatment.


      Although health insurance, ability to afford a physician visit, and foot examinations increased for Medicaid-eligible people with diabetes, there was no statistically significant difference found for other care continuum measures.
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