Predictors for retention in treatment with a UK community-based naltrexone programme for opioid dependence

Aims and method To evaluate the efficacy of naltrexone maintenance therapy in a community-based programme for opioid-dependent patients and to identify predictors for longer-term retention in treatment. A retrospective case-note study was conducted in 142 people dependent on opioids who had undergone detoxification and maintained adherence to naltrexone treatment for a minimum of 4 weeks. Social and clinical demographic factors during treatment were recorded using a standardised naltrexone monitoring scale. Efficacy was measured as retention in treatment, and potential predictors were examined using regression analysis. Results Although there was overall low retention of patients in treatment, 55.6% of the patients remained in treatment for 4-8 weeks, and 29.6% of the patients remained in treatment for 17 weeks or more. Enhanced long-term retention in treatment was associated with Asian or other minority ethnic status, employment, parental supervision of naltrexone administration, less boredom, short duration of addiction, younger age, low alcohol intake and no cannabis use in univariate analyses. Short duration of opioid dependence syndrome (3 years) and low alcohol intake (510 units/week) were significant independent predictors for longer-term retention in treatment in subsequent multivariate analysis. Clinical implications Low alcohol intake and shorter duration of addiction were significant independent predictors for longer-term retention in treatment, but retention rates for naltrexone remain low overall. Additional psychosocial support may be needed to address these issues.