Does Cannabis Use Predict Treatment Failure in Methadone-maintenance Patients?
It is unclear whether cannabinoid-positive urine specimens in heroin-dependent outpatients predict other drug use or impairments in psychosocial functioning, and whether such outcomes are better predicted by cannabis-use disorders than by cannabis use itself. IRP scientists have completed retrospective analyses of three clinical trials conducted in an urban outpatient methadone clinic. Each trial included a behavioral intervention (contingency management) for cocaine or heroin use during methadone maintenance, lasted 25-29 weeks, and had follow-up evaluations at 3, 6, and 12 months posttreatment. Data were pooled across trials where appropriate. Four hundred and eight polydrug abusers meeting methadone-maintenance criteria were categorized as nonusers, occasional users, or frequent users of cannabis based on thrice-weekly qualitative urinalyses. Cannabis-use disorders were assessed with the Diagnostic Interview Schedule III-R. Outcome measures included proportion of cocaine- and opiate
