The impact of harm-reduction-based methadone treatment on mortality among heroin users

OBJECTIVES: The purpose of this study was to investigate the impact of harm-reduction-based methadone programs on mortality among heroin users. METHODS: A prospective cohort investigation was conducted among 827 participants in the Amsterdam Cohort Study. Poisson regression was used to identify methadone maintenance treatment characteristics (dosage, frequency of program attendance, and type of program) that are significantly and independently associated with mortality due to natural causes and overdose. RESULTS: From 1985 to 1996, 89 participants died of natural causes, and 31 died as a result of an overdose. After adjustment for HIV and underweight status, there was an increase in natural-cause mortality among subjects who left methadone treatment (relative risk RR = 2.38, 95% confidence interval CI = 1.28, 4.55). Leaving treatment was also related to higher overdose mortality, but only among injection drug users (RR = 4.55, 95% CI = 1.89, 10.00). CONCLUSIONS: Harm-reduction-based methadone treatment, in which the use of illicit drugs is tolerated, is strongly related to decreased mortality from natural causes and from overdoses. Provision of methadone in itself, together with social-medical care, appears more important than the actual methadone dosage.