Medicaid programs responded to the opioid crisis by expanding treatment coverage and reforming delivery systems. We assessed whether Virginia's Addiction and Recovery Treatment Services (ARTS) program, implemented in April 2017, influenced emergency department and inpatient use. Using claims for January 2016-June 2018 and difference-in-differences models, we compared beneficiaries with opioid use disorder before and after ARTS implementation to beneficiaries with no substance use disorder. After program implementation, the likelihood of having an emergency department visit in a quarter declined by 9.4 percentage points (a 21.1 percent relative decrease) among beneficiaries with opioid use disorder, compared to 0.9 percentage points among beneficiaries with no substance use disorder. Similarly, the likelihood of having an inpatient hospitalization declined among beneficiaries with opioid use disorder. In contrast to other states, Virginia has a new Medicaid expansion population whose beneficiaries enter a delivery system in which reforms of the addiction treatment system are well under way.
Keywords: Access and use; Access to care; Addiction; Drug use; Emergency departments; Health policy; Hospital care; Medicaid; Medicaid services; Opioid use disorder.