PROJECT SUMMARY/ABSTRACT The use of benzodiazepines, an addictive yet commonly prescribed class of drugs in the US, is independently linked to serious health outcomes, including falls and fractures. Benzodiazepines are also frequently involved in opioid-related overdoses, underscoring their relevance in the ongoing US opioid epidemic. Benzodiazepine coverage restrictions and other regulatory actions have been implemented in the past to reduce benzodiazepine use and related harms, though the intended and unintended impact of these actions remains unclear. One such restriction with national implications was the exclusion of benzodiazepines coverage for Medicare enrollees during the implementation of Medicare Part D in 2006. At the same time, the Tennessee Medicaid (TennCare) program instituted a restriction on benzodiazepine coverage for all enrollees. TennCare was the only State Medicaid program in the country to do so. Thus, TennCare enrollees (including dual- eligibles) did not have benzodiazepine coverage from either Medicaid or Medicare from 2006 through 2013, when the restriction was partially removed, and then completely removed in 2014. This intermittent restriction and subsequent reintroduction of benzodiazepine coverage is unique to TennCare enrollees and provides the setting for a natural experiment to determine the impact of benzodiazepine restrictions on benzodiazepine- related harms and the use of other psychotropic medications. The proposed work will use retrospective longitudinal TennCare data linked to Medicare Part D, Vital Records, and State hospitalization data to examine three specific aims: Aim 1: To test the hypothesis that benzodiazepine restrictions in 2006 led to a lower rate of falls, fractures and opioid-related overdoses among TennCare patients with indications for benzodiazepines use compared to patients without indications for benzodiazepines. Aim 2: To test the hypothesis that the implementation and subsequent removal of benzodiazepine restrictions in 2006 and 2014 led to compensatory changes in the rates of filled prescriptions for other similarly indicated psychotropic medications among TennCare patients with indications for benzodiazepine use. Aim 3: To test the hypothesis that the removal of benzodiazepine restrictions in 2014 led to a higher rate of falls, fractures and opioid-related overdoses among patients with indications for benzodiazepine use compared to patients without indications for benzodiazepine use. To inform the proposed work and the development of an independent research program focused on drug safety research, the candidate has identified mentors with relevant expertise to oversee additional training opportunities in (1) the application of advanced difference-in-difference designs for the evaluation of state policy changes, (2) the clinical needs and barriers to care among patients that use benzodiazepines and other psychotropic drugs, and (3) the large-scale linkage of claims data with other cli...