Cost of drug use and criminal involvement before and during methadone treatment.

AIMS: To examine criminal behaviour in methadone clients as a function of expenditure on illicit drugs. To quantify the benefit of treatment for this group and to identify individuals who do not reduce criminal behaviour or substance use as a consequence of treatment. DESIGN: Cross-sectional examination of key methadone-treatment variables (age, methadone dose and length of time in treatment), and self-reported levels of spending on illicit drugs before and during methadone treatment. SETTING: All interviews were conducted in the community-based treatment centre of the Maudsley's addiction treatment services in South London. PARTICIPANTS: One hundred consecutive opiate-dependent attenders at a community treatment clinic. MEASUREMENTS: Data were collected using a self-report questionnaire and treatment characteristic data were collected from clinical case notes. FINDINGS: There was a major overall reduction in spending on illicit drugs from before treatment to during treatment, consistent with previous findings; however, 15% of the sample either showed no change or actually increased their spending after entry to treatment. This group did not differ in terms of key treatment characteristics (age, methadone dose and length of time in treatment) and there was no significant correlation between levels of spending before and during treatment. CONCLUSIONS: Despite substantial overall benefit, there is a subgroup of individuals for whom long-term treatment, even on high range doses of methadone, has no beneficial effect on criminal activity or drug use. Further research is required to establish the dynamics of this indirect treatment-benefit, and to explore the apparent resistance to treatment of the criminal behaviour of a small sub-group.