AIMS: Trials in Switzerland, the Netherlands and Spain have found that heroin-assisted treatment (HAT) as maintenance treatment for opioid-dependent patients reduces illicit drug use. A German trial also found diamorphine treatment to be superior to methadone treatment. The present study describes the association between 2 years of heroin treatment and improvements in health and social stabilization, as well as illicit drug use. DESIGN: A prospective cohort study design. PARTICIPANTS: A total of 515 patients were assigned to diamorphine treatment; 278 patients remained in the study treatment for the entire period of 24 months (54.8%). MEASUREMENTS: The results on physical (Opiate Treatment Index Health Symptoms Scale) and mental (Symptom Checklist 90-Revised Global Severity Index) health and illicit drug use (number of days with drug use within the last month-European Addiction Severity Index) were examined by repeated-measures analyses. FINDINGS: Symptoms of physical (Pillai's trace = 0.837, df = 4, P <0.001) and mental health (Pillai's trace = 0.450, df = 4, P <0.001) improved during treatment. Street heroin use declined rapidly (Pillai's trace = 0.836, df = 4, P <0.001), as did cocaine use (Pillai's trace = 0.280, df = 4, P <0.001). CONCLUSIONS: HAT is associated with improvements in mental and physical health in the long term.
