Disparities in Completion of Substance Abuse Treatment between and within Racial and Ethnic Groups

Concern about disparities in substance abuse treatment (SAT) outcomes among racial/ethnic groups in the United States has led to efforts to identify differences in substance abuse patterns and response to treatment. Yet this research has focused on between-group differences, mainly of African Americans and Whites (see Grella and Joshi 1999; Smith and Weisner 2000; Green et al. 2002; Hser et al. 2003, 2004; Satre, Mertens, and Weisner 2004), with little attention to differences between these two groups and Latinos, the fastest growing population in SAT (Morgenstern and Bux 2003; Marsh et al. 2009; Guerrero et al. 2012). The few comparative studies that include Latinos (Marsh et al. 2009) also obfuscate service and psychosocial factors within these groups that may significantly impact their ability to complete treatment. Using multicross-sectional annual data (2006–2009) from adult participants who received treatment for the first time in Los Angeles County, this study tests the extent to which between- and within-group differences in individual and program characteristics exist for African American, Latino, and White clients, and how these differences interact with treatment completion in outpatient settings. Successful completion of SAT is a well-established process outcome measure associated with long-term outcomes, such as less future criminal involvement and fewer readmissions (Evans, Li, and Hser 2009; Garnick et al. 2009). As such, this measure is particularly relevant for clients during their first exposure to treatment because successful completion reflects achievement of treatment goals at the client level and, under health care reform legislation, it may become a prevalent measure of program performance at the system level (Arndt 2010; Borys 2011). By examining individual- and service-level measures for an adequate sample of first-time clients, mainly those referred by the criminal justice system, this study involved a comparative analysis of the impact these factors have on treatment completion across racial/ethnic groups. Conceptual Framework Most research on SAT disparities across the United States has focused on individual factors to explain group differences in treatment completion between minorities and Whites. This research has highlighted the factors such as differences in client demographics, primary substance used, and addiction severity (Jacobson, Robinson, and Bluthenthal 2007a,b; Arndt 2010). In particular, findings from the national Treatment Episode Data Set pointed to seven client characteristics associated with a higher likelihood of successfully completing SAT: (1) non-Latino White, (2) female, (3) older than 40, (4) more than 12 years of education, (5) employed, (6) use of alcohol as primary substance, and (7) less than daily substance use at admission (Substance Abuse and Mental Health Services Administration [SAMHSA] 2009). Specifically, primary drug used and severity of drug use at intake, as well as psychosocial stressors, are individual factors associated with higher risk to drop out of treatment. Studies show that use of heroin, methamphetamine, and cocaine compared with alcohol is associated with reduced likelihood of treatment completion (Bluthenthal, Jacobson, and Robinson 2007; SAMHSA 2009). In Los Angeles County in 2006, African Americans were most likely to report using cocaine/crack than other drugs, Latinos were most likely to report using heroin, and Whites were most likely to report using amphetamine (Bluthenthal, Jacobson, and Robinson 2007). In addition, it is well documented that African Americans and Latinos enter treatment with more health, mental health, and social problems than Whites, which can contribute to reduced treatment completion (Marsh et al. 2009). Overall, the aggregate effect of primary drug used and severity of drug use, as well as the prevalence of mental health problems and homelessness, place minorities at a disadvantage in terms of successfully meeting the demands of a structured treatment program (Grella and Stein 2006; Ngo et al. 2009; Niv, Pham, and Hser 2009; Van Dorn, Swanson, and Swartz 2009). Thus, Hypothesis 1 posited that after accounting for primary drug used and days of drug use before admission, as well as history of mental disorder and homelessness status, African American and Latino clients would report lower odds of completing treatment compared with White clients. The literature on treatment completion has also suggested that minority status and primary drug used, such as cocaine, methamphetamine, and heroin compared with alcohol, are interacting factors associated with lower odds of completing treatment (Bluthenthal, Jacobson, and Robinson 2007; SAMHSA 2009). Thus, Hypothesis 2 posited that African Americans and Latinos using cocaine, methamphetamine, and heroin as their primary drug problem would be less likely to complete treatment than Whites and individuals using alcohol. It is well established that African American and Latinos face significant challenges to accessing and remaining in treatment long enough to complete treatment successfully (McKay et al. 2003; Tonigan 2003). However, emerging evidence has highlighted significant heterogeneity within African Americans and Latinos in terms of primary drug of choice, severity of drug use before admission, and prevalence of psychosocial stressors that may inhibit efforts to meet treatment goals (Arndt 2010; Guerrero et al. 2012). Thus, Hypothesis 3 posited that use of illegal drugs as primary drug problem, days of drug use before admission, history of mental disorder, and homelessness status would be associated with lower odds of completing treatment within members of each racial and ethnic group. There is growing recognition of the significant role of specific substance abuse treatment services and system factors in helping individuals achieve treatment completion (Marsh et al. 2009; Marsh, Shin, and Cao 2010). Among those seeking help for substance abuse issues, wait time to treatment entry is the most commonly cited service barrier (Claus and Kindleberger 2002; Appel et al. 2004), whereas unmet service needs are generally factors associated with a reduced likelihood for African Americans and Latinos to complete treatment (Jacobson, Robinson, and Bluthenthal 2007a; Marsh et al. 2009; Niv, Pham, and Hser 2009; Shim et al. 2009). Increasing evidence also suggests that referral source is related to treatment completion (SAMHSA 2009). In particular, drug and probation court referrals to SAT have aimed to facilitate rapid access to social services to achieve timely completion of treatment as a condition of probationary status (Evans, Li, and Hser 2008, 2009). Although African Americans and Latinos are disproportionally represented in the criminal justice system, it is not clear whether individuals benefit from rapid access to treatment and the additional supervision that court referrals offer to ensure successful completion of substance abuse treatment. Thus, Hypothesis 4 posited that fewer days of wait time to treatment entry and referral by the criminal justice system would be associated with higher odds of completing treatment for all members of racial and ethnic groups.