Predictors of the successful treatment of addiction to heroin and other illicit opioids. Systematic review

BACKGROUND: Dependence on heroin (and other illicit opioids) is a serious health and social problem. In the Czech Republic, there are an estimated 4,500 problem heroin users and 7,100 users of diverted buprenorphine (especially Subutex®). Users of heroin and other opioids are the second largest group of drug users in treatment. The treatment of opioid dependence involves psychosocial (abstinence-based) and/or pharmacological (substitution treatment) interventions. METHODS: Systematic review. Specialised databases (ScienceDirect, Scopus, Cochrane Database) and other sources (Medvik) were searched for both international and Czech scientific literature on the treatment of addiction to heroin (or other illegal opiates) and factors influencing its outcomes (published between 2000 and 2017). CONCLUSIONS: The basic positive predictors are the length of treatment and specific sociodemographic (such as age at entry to treatment) and psychological characteristics. Psychiatric comorbidity is generally a risk factor. The pressure of the client’s conflicts with the law also improves retention in treatment and its overall outcome. Another positive predictor is a family situation with no major conflicts and the absence of addiction issues among client’s family members. Substitution treatment was found to show higher treatment retention rates than abstinence-based psychosocial therapy. The success of substitution treatment is associated with higher doses of substitution medicines, psychosocial support during treatment and good relationships with the service staff. Taking other drugs during treatment was found to cause a deterioration of the outcomes. Users of opioids other than heroin and non-injecting users seem to achieve better treatment outcomes.