Project Summary The burden of kidney failure, a life-threatening condition that afflicts nearly 750,000 Americans, falls disproportionately on the most socially disadvantaged communities in the US. Inadequate access to care and lack of health insurance coverage are critical drivers of racial/ethnic and socioeconomic disparities in the incidence of kidney failure and outcomes after initiating kidney replacement therapy. In our current grant (R01DK113298), we found that, among nonelderly patients initiating dialysis, Medicaid expansions under the Affordable Care Act (ACA) reduced uninsurance, increased the likelihood of starting long-term hemodialysis with maturing or functional arteriovenous access, and lowered one-year mortality. Compared with white patients, Black patients experienced a 3-fold greater absolute decline in mortality following expansion. Although there is a growing evidence base of the impact of Medicaid expansion on access to care and health, these prior studies have examined a period of sustained economic growth and declining rates of uninsurance. But the effects of expanded Medicaid coverage may be magnified during times of economic distress. During the first six weeks of the COVID-19 pandemic, an unprecedented forty million Americans have filed unemployment benefits, with expectations of stark coverage losses, particularly in nonexpansion states. Moreover, death rates from COVID-19 are higher in racial/ethnic minority populations and among patients with chronic conditions, including kidney disease. The pandemic has also disrupted care, with potential adverse consequences for populations with complex medical needs and social risk factors. National estimates of the impact of COVID-19 and expanded Medicaid coverage on access to care and outcomes are needed to inform effective public health responses. This R01 renewal application will examine disparities in coverage, access to care, transplant evaluation, and mortality among patients with kidney failure during and after the pandemic (Aim 1), as well as the protective role of Medicaid expansion on disparities in treatment and outcomes of kidney failure (Aim 2), and incidence (Aim 3). The rationale for our study is that the COVID-19 pandemic presents fundamental threats to access to care and health outcomes for persons with kidney disease, but expanded Medicaid coverage may attenuate these effects, reduce racial/ethnic and socioeconomic disparities, and therefore inform health policy. We innovate by geolocating address data for incident ESKD patients, thereby deriving granular information on neighborhood disadvantage, modeling incidence within small geographic areas, and identifying patients living in areas with high infection rates. Further, we consider the long-term effects of Medicaid expansion on disparities in transplantation and home dialysis, two alternatives to hemodialysis prioritized by the 2019 Advancing American Kidney Health Executive Order. We expect that this proposal ...