ResearchPosted on rand.org Jul 15, 2026Published in: Journal of Substance Use and Addiction Treatment, Volume 188, 209997 (September 2026). DOI: 10.1016/j.josat.2026.209997
Among individuals with opioid use disorder (OUD) and co-occurring mental illness, stimulant co-use may be associated with more severe symptoms and less treatment utilization. We sought to understand the association of stimulant use with social needs and OUD and mental illness severity and treatment.
This cross-sectional study used baseline data from a randomized controlled trial of collaborative care for primary care patients with OUD and co-occurring depression and/or posttraumatic stress disorder (PTSD). We categorized stimulant use (cocaine/methamphetamine) into daily use (20 or more days), non-daily use (1-19 days), and no use (0 days). We conducted comparisons across measures of social needs and OUD and mental illness severity and treatment through one-way analysis of variance for continuous variables and chi-square tests for categorical/binary variables.
123 (15.4%) participants used stimulants daily, 164 (20.6%) reported non-daily use, and 510 (64%) used no stimulants. When comparing participants by stimulant use, we found differences in education (p = 0.020), housing status (p < 0.001), legal problems (p < 0.001), recent overdose (p < 0.001), overdose risk (p < 0.001), MOUD use (p < 0.001), depression/PTSD symptoms (p < 0.001), and receipt of therapy (p = 0.004) or medication (p < 0.001) for depression/PTSD with all differences demonstrating more unmet social needs, greater OUD and mental illness severity, and lower treatment utilization for participants using stimulants.
Among primary care patients with OUD and co-occurring depression/PTSD, individuals using stimulants experienced a higher disease burden and decreased utilization of care across multiple measures. These associations suggest that clinicians should specifically address stimulant use in the context of co-occurring OUD and mental illness.
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