Contents lists available at ScienceDirect Drug and Alcohol Dependence journal homepage: www.elsevier.com/locate/drugalcdep Full length article Treatment outcome disparities for opioid users: Are there racial and ethnic differences in treatment completion across large US metropolitan areas? Gerald J. Stahler ⁎ , Jeremy Mennis Department of Geography and Urban Studies, Temple University, (025-27), 309 Gladfelter Hall, Philadelphia, PA 19122, United States ARTICLE INFO Keywords: Treatment completion Disparities Treatment outcomes Metropolitan areas Opioid users ABSTRACT Background: The present study examined racial/ethnic disparities in initial treatment episode completion for adult clients reporting opioids as their primary problem substance in large US metropolitan areas. Methods: Data were extracted from the 2013 TEDS-D dataset (Treatment Episode Dataset-Discharge) for the 42 largest US metropolitan statistical areas (MSAs). Fixed effects logistic regression controlling for MSA was used to estimate the effect of race/ethnicity on the likelihood of treatment completion. The model was repeated for each individual MSA in a stratified design to compare the geographic variation in racial/ethnic disparities, controlling for gender, age, education, employment, living arrangement, treatment setting, medication-assisted treatment, referral source, route of administration, and number of substances used at admission. Results: Only 28% of clients completed treatment, and the results from the fixed effects model indicate that blacks and Hispanics are less likely to complete treatment compared to whites. However, the stratified analysis of individual MSAs found only three of the 42 MSAs had racial/ethnic disparities in treatment completion, with the New York City (NYC) MSA largely responsible for the disparities in the combined sample. Supplementary analyses suggest that there are greater differences between whites and minority clients in the NYC MSA vs. other cities on characteristics associated with treatment completion (e.g., residential treatment setting). Conclusion: This study underscores the need for improving treatment retention for all opioid using clients in large metropolitan areas in the US, particularly for minority clients in those localities where disparities exist, and for better understanding the geographic context for treatment outcomes. 1. Introduction 1.1. Background Illicit opioid use represents one of the most harmful drug problems globally, responsible for an estimated 70% of the world’s burden of disease attributable to drug use disorders as well as 66% of the 63,632 US drug overdose deaths in 2016 (Seth et al., 2018; United Nations Office on Drugs and Crime (UNODC, 2017). Although the US is the global leader in both absolute numbers (one quarter of the world’s total) and rates of overdose deaths, other nations such as Canada, Australia, Ireland, Turkey, England, Wales, and Scotland have all seen recent substantial increases in overdose mortality, primarily due to opioids (European Monitoring Centre for Drugs and Drug Addiction (EMCDDA, 2017a; United Nations Office on Drugs and Crime (UNODC, 2017). An important pillar for policy strategies to address the current opioid overdose crisis has been to provide increased access and capacity for treatment for those with opioid use disorders (OUDs) (Evans and Farrelly, 2017; Franklin et al., 2015; Murphy et al., 2016). One of the most widely used proximal measures of treatment effectiveness for substance use disorders (SUDs) is treatment completion (Brorson et al., 2013), generally defined as successfully completing treatment goals (Greenfield et al., 2007). Despite evidence showing sustained recovery may involve multiple episodes over time (Guerrero, 2013; McKay and Weiss, 2001), individual treatment completion episodes can serve as an important indicator associated with longer term abstinence, fewer re- lapses, higher levels of employment, higher wages, fewer readmissions, less future criminal involvement, and better health (Brorson et al., 2013). Black and Hispanic people in the US tend to have lower treatment utilization rates, greater barriers to receiving treatment, and poorer outcomes, including treatment completion, compared to white clients (Alegría et al., 2006, 2011; Arndt et al., 2013; Guerrero et al., 2013a; National Research Council, 2003; Saloner and Le Cook, 2013). Simi- larly, in Europe, there has been a recent recognition that ethnic minorities, migrants, refugees, and asylum seekers who have substance https://doi.org/10.1016/j.drugalcdep.2018.06.006 Received 10 January 2018; Received in revised form 1 June 2018; Accepted 4 June 2018 ⁎ Corresponding author. E-mail addresses: jstahler@temple.edu (G.J. Stahler), jeremy.mennis@temple.edu (J. Mennis). Drug and Alcohol Dependence 190 (2018) 170–178 Available online 11 July 2018 0376-8716/ © 2018 Elsevier B.V. All rights reserved. T