PROJECT SUMMARY Among the 5+ million Medicare beneficiaries living with Alzheimer's disease and related dementias (ADRD), one-quarter are dually enrolled in Medicaid. Medicaid is a needs-based insurance program that covers long- term services and supports and Medicare out-of-pocket costs. Almost one third of low-income older adults who join Medicaid lose Medicaid coverage within a year. Even though older adults may remain eligible for Medicaid, failing to complete complicated eligibility redetermination paperwork can lead to loss of benefits. However, during the COVID-19 pandemic, a temporary federal policy guaranteed continuous Medicaid coverage by suspending disenrollments due to Medicaid redeterminations. The end of this protection in 2023 put 1+ million Medicare beneficiaries living with ADRD at risk for losing Medicaid coverage. Even though Medicaid is the nation's primary source of financial assistance with health care and long-term care costs, there is limited evidence on how losing Medicaid coverage affects people living with ADRD and their health outcomes. This gap in knowledge is concerning given the projected increase in the number of people living with ADRD, a large proportion of whom will qualify for Medicaid. The long-term goal of our research is to improve access to care and services for low-income older adults living with dementia. The objective of this project is to identify predictors of retaining Medicaid coverage for people living with ADRD and to learn how federal Medicaid policy changes affected the health of people living with ADRD. Our central hypotheses are that 1) losing Medicaid coverage will be more common for people living with ADRD and will vary by residential setting; and 2) federal policy changes that temporarily guaranteed Medicaid continuous coverage improved health outcomes for people living with ADRD. We will test these hypotheses through three aims that employ mixed methods and strong quasi-experimental research techniques: 1) Describe how Medicaid retention differs for older adults with an ADRD diagnosis across settings; 2) Estimate the effect of retaining Medicaid coverage among older adults with ADRD on health outcomes; 3) Estimate the effect of ending Medicaid continuous coverage policies among older adults with ADRD on health outcomes. The findings from this research will inform policymakers and community organizations' decision-making around the ways to increase Medicaid participation and ensure optimal health outcomes for people living ADRD. Further, this research aligns with a top research priority identified by the National Academy of Medicine to improve quality of life for people with ADRD by reducing financial stressors and enabling access to key services. Specifically, the findings from this work will provide novel evidence on the effects of Medicaid participation and its role in supporting access to long-term care services and medical care among people with ADRD.