Medicaid Expansions and Participation in Supplemental Security Income by Noncitizens.

Abstract

<b>Objectives.</b> To estimate the effect of Medicaid expansion on noncitizens' and citizens' participation in the Supplemental Security Income (SSI) program. The Affordable Care Act (ACA) expanded Medicaid eligibility to cover low-income nonelderly adults without children, thus delinking their Medicaid participation from participation in the SSI program.<b>Methods.</b> Using data from the Social Security Administration for 2009 through 2018 (n = 1020 state-year observations) and the Current Population Survey for 2009 through 2019 (n = 78 776 respondents), we employed a difference-in-differences approach comparing SSI participation rates in US states that adopted Medicaid expansion with participation rates in nonexpansion states before and after ACA implementation.<b>Results.</b> Medicaid expansion reduced the SSI (disability) participation of nonelderly noncitizens by 12% and of nonelderly citizens by 2%. Estimates remained robust with administrative and survey data.<b>Conclusions.</b> Medicaid expansion caused a substantially larger decline in the SSI participation of noncitizens, who face more restrictive SSI eligibility criteria, than of citizens. Our estimates suggest an annual savings of $619 million in the federal SSI cost because of the decline in SSI participation among noncitizens and citizens.