Swartz JA, Beltran SJ. - Researchers examined if increased prescription opioid availability is related to the higher opioid overdose-related mortality rates (OOMR) in Affordable Care Act (ACA) Medicaid expansion states vs non-expansion states. For this work, national, serial, cross-sectional data for Medicaid-reimbursed prescription opioids, Medicaid enrollment information and annual OOMR for any opioids and for prescription opioids from 49 states and the DC pre- (2008–13) and post-ACA Medicaid expansion (2014–16) were used. Medicaid expansion states vs non-expansion states had greater increases in prescription opioid availability and had higher any OOMR compared with non-expansion states. It wasn’t until 2015 and 2016 that expansion and non-expansion states showed significant differences in prescription OOMR. There is a possibility of delayed effects, but differences in post-Affordable Care Act Medicaid expansion mortality rates don’t seem mediated by increases in Medicaid-reimbursed prescription opioid availability in Affordable Care Act Medicaid expansion states.