Effectiveness of Washington State's hub and spoke model to improve opioid use disorder outcomes.

Introduction: Innovative strategies remain necessary to increase utilization of medications for opioid use disorder (MOUD), an effective approach to reduce overdoses and deaths. The hub and spoke (HS) model is increasingly used to improve MOUD treatment, yet the impact is relatively unknown. We assessed the effectiveness of Washington State's hub and spoke (WA-HS) model on 6-month outcomes of MOUD continuity and health care utilization. Methods: We analyzed 25 368 adult Medicaid beneficiaries with new MOUD episodes in 2016-2019, comparing HS and non-HS cohorts in the 6 months after starting MOUD. Results: Across both cohorts, 26% stayed on MOUD for 6 months, and within 6 months of MOUD initiation, 42% had an emergency department (ED) visit, 14% had any hospitalization, and 13% entered intensive substance use treatment. No significant differences were found between cohorts for all outcomes. Conclusion: Our null findings likely reflect the complexity of the OUD crisis, the many needs of people with OUD that require flexible approaches at the individual and systems levels, and the WA-HS focus on MOUD initiation. Findings highlight the need to ensure HS models incorporate strategies to address MOUD continuity to drive long-term recovery for people with OUD.