Swartz JA, et al. - Researchers sought to assess if higher opioid overdose-related mortality rates (OOMR) in Affordable Care Act (ACA) Medicaid expansion states vs mortality rates in non-expansion states have been mediated by increased prescription opioid availability. They determined difference-in-difference effects of time and expansion status on Medicaid-reimbursed opioids, measured in morphine milligram equivalents on all OOMR, and on prescription OOMR, using separate mixed effect regression models. For this study, they derived data for Medicaid-reimbursed prescription opioids, Medicaid enrollment information, and annual OOMR for any opioids and for prescription opioids from 49 states and the D.C. pre- (2008-2013) and post-ACA Medicaid expansion (2014-2016) using national, serial, cross-sectional data. The analysis revealed no correlation of increases in Medicaid-reimbursed prescription opioid availability in the ACA Medicaid expansion states in the US with post-ACA Medicaid expansion mortality rate differences. However, there is yet a chance of lagged effects.