Heroin use during methadone maintenance treatment: the importance of methadone dose and cocaine use.

OBJECTIVES: The purpose of this study was to examine factors associated with heroin use during methadone maintenance treatment. METHODS: Logistic regression statistical models were used to examine data obtained in a cross-sectional sample of 652 methadone patients. RESULTS: Heroin use during the 3 months prior to interview was shown to be greatest among (1) patients maintained on methadone dosages of less than 70 mg/day (adjusted odds ratio OR = 2.1, 95% confidence interval CI = 1.3, 3.4) and (2) patients who used cocaine during treatment (adjusted OR = 5.9, 95% CI = 3.8, 9.1). These results were independent of treatment duration, treatment compliance, alcohol use, and socioeconomic factors. Cocaine users were more likely than nonusers of cocaine to use heroin at all methadone dosage levels. CONCLUSIONS: This study confirms and extends past research showing high-dose methadone maintenance to be important to heroin abstinence. Further investigation of the independent association between heroin use and cocaine use is needed.