Publicly-Funded Treatment Outcomes and Their Correlates Among Clients Who Engage in Opioid-Methamphetamine Co-Use, Other Types of Polydrug Use, or Single Drug Use

<i>Background</i>: Community samples of persons entering SUD treatment suggest that polydrug use is the norm; however, patterns of polydrug use vary by individual. <i>Objectives</i>: With increasing rates of opioid-methamphetamine co-use in the U.S., examination of correlates and outcomes for substance use disorder (SUD) treatment for this type of polydrug use, comparing to other types of polydrug use and single drug use, are needed. Secondary data from 2481 adults (ages 18+) in a multi-year evaluation of publicly-funded SUD treatment was analyzed. <i>Results</i>: The study's findings show that individuals who co-used opioids and methamphetamines fared worse following entry into SUD treatment, in terms of meeting criteria for a SUD at 12-month follow-up, as well as a broader measure of recovery that takes into account living situation, mental health concerns, criminal legal involvement, social support, and subjective quality of life compared to individuals who recently engaged in other combinations of polydrug use and to individuals who used only one class of illicit drug. <i>Conclusions</i>: The current study adds to the empirical evidence that individuals who co-use opioids and methamphetamine have greater vulnerabilities, such as greater economic hardship, mental health concerns, criminal legal involvement, and interpersonal victimization. Future research is needed to examine interventions that target this distinct polydrug use pattern to reduce overdose deaths and to increase recovery success.