Pharmacy Closures and Medication Adherence Among Older Adult Medicare Part-D Beneficiaries

The objective of this project is to evaluate the impact of pharmacy closures on adherence to chronic medications among older adult Medicare Part-D beneficiaries. Although ongoing efforts focus almost exclusively on addressing individual-level barriers to medication adherence, some older adults may encounter community-level barriers, including the geographic accessibility of pharmacies, in adhering to their prescription medications. Pharmacy closures may worsen existing barriers in the geographic accessibility of pharmacies, including pharmacy deserts. Medicare Part-D policies, including low pharmacy reimbursement rates and the growth of preferred pharmacy networks that often exclude independent pharmacies, are considered a fundamental cause of such closures. Despite these insights, the impact of closures and Part-D pharmacy access policies and regulations on medication adherence is not known. Pharmacy closures may be an overlooked community-level mechanism that exacerbates the adverse consequences of pharmacy deserts on medication adherence. We propose to leverage several proprietary and public data sources, including a census of Medicare Part-D patient-level prescription claims, to assemble a longitudinal, multi-level geocoded dataset with detailed information on pharmacy locations and characteristics (e.g., preferred pharmacy status) and derive a series of novel measures, including a multidimensional county-level measure of pharmacy access within Medicare Part-D (e.g., % of pharmacies that participate in Part-D preferred networks) and conduct innovative analyses. The proposal aims to: (1) evaluate the effect of pharmacy closures on adherence to chronic medications among Medicare Part-D beneficiaries before (2014-2019) and during (2020-2022) the COVID-19 pandemic; (2) Determine the extent to which individual-level (e.g., dual-eligible, ) and community-level (e.g., distance to nearest pharmacy, rural vs. urban) characteristics modify the effect of pharmacy closures on adherence to chronic medications among Medicare Part-D beneficiaries and identify subgroups most at-risk for non-adherence post-closure and in need of pharmacy services; and (3) Investigate the impact of county-level measures of pharmacy access on medication adherence among Medicare Part-D beneficiaries at the individual-level and community-level. Our proposed work is innovative because it will be the first study to investigate the impact of pharmacy closures on medication adherence at older ages. Our analyses of multi-level causal pathways responsible for changes in medication adherence post-closure is also novel. With respect to expected outcomes, the work proposed will contribute evidence needed to advance Medicare Part-D payment and delivery reforms that reduce pharmacy closures and, in turn, improve medication adherence. These outcomes will have a positive impact given the increasingly important role of pharmacies in preventive and emergency care and will support NIA in its strategic goals in improving health at older ages.