A path analysis of cognitive, affective, and behavioral predictors of treatment response in a methadone maintenance program

Purpose: Continued illicit drug use by opioid-dependent patients maintained on methadone is a serious problem, undermining the goal of methadone maint enance treatment and increasing the risk for HIV. The current study employe d structural equation modeling (SEM) to examine cognitive affective, and be havioral predictors of treatment response during the first 12 weeks of meth adone maintenance treatment. Methods: 302 opioid-dependent individuals (72% male; 28% female) entering a methadone maintenance program (MMP) were prov ided with a comprehensive intake assessment. Heroin and cocaine use were as sessed using twice weekly urine toxicology screens. The model accounted for 37 percent of the variance in abstinence from illicit opiates and 38 perce nt of the variance in abstinence from cocaine. Results: Continued heroin us e while maintained on methadone was predicted by pre-treatment severity of addiction and by strength of self-identity as an "addict." Cocaine use was predicted by pre-treatment severity of addiction, low self-efficacy, lack o f negative affect, and strength of self-schema. The strongest predictor of abstinence from both heroin and cocaine was attendance at the adjunctive ma nual-guided psychosocial group interventions. Implications: Implications fo r treatment are discussed.