Heroin maintenance for chronic heroin dependents (Review) (2008)

BACKGROUND: Many medications have been used for stabilizing heroin users: Methadone, Buprenorphine and LAAM. The present review focus on the prescription of heroin to heroin dependents.
OBJECTIVES: To assess the efficacy and acceptability of heroin maintenance versus methadone or other substitution treatments for opioid dependence, in retaining patients in treatment; reducing the use of illicit substances and improving health and social functioning.
SEARCH STRATEGY: The Cochrane Central Register of Trials (CENTRAL) issue 1, 2005; MEDLINE 1966-2005, EMBASE 1980-2005 and CINAHL till 2005 (on OVID) were searched. There was no language or publication year restrictions. Many researchers were contacted for information.
SELECTION CRITERIA: Randomised controlled trials of heroin (alone or combined with methadone) maintenance treatment compared with any other pharmacological treatments for heroin dependents.
DATA COLLECTION AND ANALYSIS: The trials were independently assessed for inclusion and methodological quality by the reviewers. Data were extracted independently and double checked. Studies were not pooled together because of heterogeneity.
MAIN RESULTS: 2400 references were obtained and 20 studies were eligible, 4 met the inclusion criteria for a total of 577 patients. The studies could not be analysed cumulatively because of heterogeneity of interventions and outcomes. Retention in treatment: no groups difference was found in two studies; one study (N=96) found RR=2.82 (95% CI 1.70-4.68) favouring heroin; one study (N=235) found RR 0.79 (95%CI 0.68-0.90) favouring methadone. Relapse to illegal heroin use (self- reported): in one study people using heroin in treatment was 64% (heroin group)and 59% (methadone group); in the other study the RR of heroin use was 0.33 (95%CI 0.15-0.72) favouring heroin. Criminal offence: one study showed the potential of heroin prescription in reducing the risk of being charged RR 0.32 (95% CI 0.14-0.78). Social functioning: two studies did not show statistical difference between intervention groups, and two studies considered criminal offence and social functioning as part of a multidomain outcome measure showing improvements among those treated with heroin plus methadone over those on methadone only.
AUTHORS' CONCLUSIONS: No definitive conclusions about the overall effectiveness of heroin prescription is possible. Results favouring heroin treatment come from studies conducted in countries where easily accessible Methadone Maintenance Treatment at effective dosages is available. In those studies heroin prescription was addressed to patients who had failed previous methadone treatments. The present review contains information about ongoing trials which results will be integrated as soon as available. (Author' s abstract)