Abstract
OBJECTIVE: To determine whether delivery of opioid use disorder (OUD) treatment through a hub and spoke (HS) model is associated with better adherence to psychotropic medication treatment, compared to usual treatment. Washington State’s HS model required each network to include at least one mental health program, so we hypothesized that it would improve psychotropic medication adherence for people with both a mental health disorder (MHD) and an OUD. METHODS: The study sample comprises adult Medicaid beneficiaries who had a diagnosis of depression or bipolar disorder in Washington during 2017–2019, who also received medication treatment for OUD. We computed rates for receipt of and adherence to relevant psychotropic medication, before and after regression-based adjustment for patient characteristics with propensity score weighting to mitigate potential selection effects. The key exposure was treatment at a HS program. RESULTS: Patients with bipolar disorder who were seen in HS programs were less likely than other patients to fill a mood stabilizer prescription in the 30 days post-index (predicted probability (PP)=11.2% versus 17.8%, p=0.012). However, the likelihood of achieving 80% adherence to mood stabilizers in the year post-index was higher among HS patients (21.6% versus 5.9%, p=0.01). HS participation was not associated with depression treatment outcomes. CONCLUSION: HS participation does not appear to be associated with greater psychotropic medication use or adherence among patients with depression, while effects for bipolar disorder are mixed. It appears that the HS model’s focus on OUD treatment initiation did not generate much positive spillover for ongoing psychotropic medication treatment.