NDARC Technical Report No. 191 (2004)
Introduction: Heroin dependence is remarkably persistent and is, in many cases, a lifelong condition, yet the long term outcome following treatment for heroin dependence is rarely studied and has not yet been systematically studied in Australia. Better understanding of the long term outcomes in terms of mortality, drug use patterns, criminality and psychiatric comorbidity has the potential to guide more effective interventions and public health responses both nationally and internationally.
The Australian Treatment Outcome Study (ATOS) is the first large scale longitudinal treatment outcome study of persons with heroin dependence to be conducted in Australia. ATOS is coordinated by the National Drug and Alcohol Research Centre (NDARC), and is conducted in collaboration with the Drug and Alcohol Services Council (DASC) and Turning Point Alcohol and Drug Centre.
The aims of ATOS are:
- To describe the characteristics of people seeking treatment for problems associated with heroin use in Australia;
- To describe the treatment received; and
- To examine treatment outcomes and costs at 3 and 12 months after commencement of treatment.
The current report presents data from the 12 month follow-up interview of subjects in the New South Wales arm of the study.
Method: Nineteen treatment agencies were randomly selected from within the three main treatment modalities (methadone/buprenorphine maintenance therapy; detoxification; residential rehabilitation) stratified by area health service. Five hundred and thirty five individuals entering treatment and 80 heroin users not seeking treatment were recruited into the study and interviewed by NDARC staff using a structured questionnaire. A total of 495 individuals were re-interviewed at 12 months, 80% of the original sample. 442 (83%) of the treatment sample and 53 (66%) of the non-treatment sample were successfully recontacted and interviewed at 12 months. A further 31 participants were incarcerated, and 5 deceased at 12 month follow-up. Data was collected on a variety of domains including: treatment experiences; heroin and other drug use, mental health and criminal activity.
- There were no differences between those re-interviewed and those lost to follow up in terms of heroin use at baseline, treatment history or criminal involvement suggesting the sample re-interviewed is broadly representative of the original cohort.
- There were substantial reductions in heroin and other drug use across all three treatment samples. The majority of those who had entered treatment were abstinent from heroin at 12 months (MT 68%, DTX 54%, RR 69%). While there was also an increase in one month abstinence in the non treatment sample, this was considerably less at 25%.
- While current heroin use remained low among the treatment groups, the majority in all groups had used heroin within the 12 months (MT 83%, DTX 92%, RR 74%, NT 100%).
- The reduction in heroin use in the treatment samples was paralleled by reductions in the use of other drugs, suggesting individuals were not substituting heroin use with other drug use to any significant degree.
- There were notable reductions in the percentages of subjects reporting committing any crime or that their major source of income was from crime across the treatment samples.
Conclusion: The high rate of sample retention at 12 months is of an international standard and lends validity to the findings. The study attests to the fact that heroin users may be successfully engaged in longitudinal studies. Substantial reductions in drug use, risk-taking, crime and psychopathology among the treatment groups were noted, as were improvements in physical health. Compared to the NT group, participants in the treatment groups had lower levels of drug use, risk-taking and crime. Seventy two per cent of the NT group had enrolled in treatment since baseline, therefore comparisons indicating the benefits of treatment are conservative. Overall, at 12 months the general functioning of the treatment groups had substantially improved since baseline.