Though a life-saving medication (Degenhardt et al., 2023, Mattick et al., 2014, Nielsen et al., 2022, Sordo et al., 2017), only 22% of the estimated 2.4 million people in the United States living with Opioid Use Disorder (OUD) received medication for OUD (MOUD) in 2021(Jones et al., 2023). While extended release intramuscular naltrexone can support relapse prevention after opioid abstinence, buprenorphine (Schedule III medication, partial opioid agonist, 36-48 hour half-life (Walsh et al., 1994)) and methadone (Schedule II medication, full opioid agonist, 24-48 hour half-life (Walsh et al., 1994)) are recommended for opioid withdrawal and maintenance phases by the Substance Abuse and Mental Health Services Administration (Center for Behavioral Health Statistics and Quality - Substance Abuse and Mental Health Services Administration SAMHSA 2021), American Society of Addiction Medicine (Cunningham et al., 2020), and the Veterans Affairs(VA)/Department of Defense (DoD) guidelines (Perry et al., 2022). Meta-analyses indicate outcomes of buprenorphine and methadone may vary by medication doses, fixed versus flexible doses, and specified outcomes; but similar MOUD retention rates and illicit substance (opioid) use when buprenorphine and methadone are prescribed with fixed and/or medium-to-high doses (Hutchison et al., 2023, Klimas et al., 2021, Mattick et al., 2014). A recent meta-analysis of MOUD outcomes in United States studies found that MOUD treatment retention was higher in studies that offered a single medication (e.g., methadone or buprenorphine only), relative to studies that offered participants a choice between MOUD options (Hutchison et al., 2023). Buprenorphine has a lower risk of neonatal adverse outcomes for patients taking it while pregnant (Suarez et al., 2022) and can be prescribed on an outpatient basis (e.g., 30-day supply). Methadone must be prescribed daily or near-daily at a licensed clinic for patients with less than a year of MOUD therapy, after which 14-day (1 year time-in-treatment) and 31-day (2 years time-in-treatment) take-home prescriptions can be offered (Substance Abuse and Mental Health Services Administration (SAMHSA), 2023a). Despite guidance, MOUD prescribing remains persistently suboptimal (Essien et al., 2020; Substance Abuse and Mental Health Services Administration (SAMHSA), 2021a, b) and inequitable (Center for Behavioral Health Statistics and Quality - Substance Abuse and Mental Health Services Administration (SAMHSA), 2021; Essien et al., 2020; Lagisetty et al., 2019; Manhapra et al., 2016; Manhapra et al., 2020)

Racialized inequities in MOUD prescribing and outcomes are documented within federal insurance and healthcare systems, such as patients enrolled in Medicare (Jones et al., 2022) and VA healthcare (Essien et al., 2020, Manhapra et al., 2016, Manhapra et al., 2020). White VA enrollees are more likely to initiate MOUD within 30 days of an opioid overdose, relative to Black or Latinx enrollees (Essien et al., 2020). Black VA enrollees are more likely to be started on methadone (Essien et al., 2020); whereas VA enrollees receiving buprenorphine for OUD are disproportionately younger and white (Manhapra et al., 2016, Manhapra et al., 2020). Systemic racism in MOUD receipt may have been exacerbated, in part, by the recently repealed buprenorphine-related policy requiring prescriber waivers and limiting patient:prescriber ratios (Substance Abuse and Mental Health Services Administration (SAMHSA), 2023b). The historic policy likely led, in part, to what the Substance Abuse and Mental Health Services Administration refers to as a ‘two-tiered treatment system’ in MOUD receipt (Substance Abuse Mental Health Services Administration, 2020).

The MHS is one of the largest healthcare systems in the US, providing direct care to approximately 7.5 million TRICARE beneficiaries annually (1.4 million active duty service members, 2 million of their family members, and 4.1 million retirees, their family members, and survivors) across more than 500 hospitals and clinics in the US and abroad in 2021 (US Department of Defense, 2023). When services are unavailable in-house, TRICARE beneficiaries enrolled for care in a military treatment facility can be referred to civilian healthcare providers as part of their covered benefits. Data regarding OUD and MOUD in the MHS is limited. One analysis found the rate of OUD to be approximately 6.7 per 10,000 from 2016-2021 in active duty service members (Moore et al., 2023) and another found that most patients in the MHS with OUD prescribed buprenorphine received such prescriptions by a provider outside of a military treatment facility (Issa et al., 2021).

Due to DoD policy implications, MOUD initiation in active duty service members may have increased complexities. While one DoD policy indicates that the goal of substance use treatment for active duty service members is to “return DoD personnel to full duty,” (US Department of Defense, 2020) MOUD can limit deployability and OUD not in remission and/or active enrollment in service-specific substance use disorder programs is not eligible for a waiver to deploy. Extended periods of non-deployable status can negatively impact a service member’s career and lead to administrative military discharge (Office of the Under Secretary of Defense for Personnel and Readiness, 2021). This dilemma may explain why only 10% of active duty service members with chronic pain and OUD in this limited sample received buprenorphine or injectable naltrexone, albeit methadone and oral naltrexone receipt was unknown (Hepner et al., 2022).

Given the documented inequities in other federal systems and the additional complexities of DoD policies related to MOUD, the objective of this study was to conduct a comprehensive evaluation of MOUD prescribing practices for patients diagnosed with OUD within the MHS. It was hypothesized that the MOUD initiation rate would be between 10-19% and that Black and Latinx patients would be less likely to receive MOUD, relative to white patients.