Meta-analysis Confirms Methadone Maintenance Reduces Illicit Opioid Use and Improves Treatment Retention in Patients with Opioid Dependence

Methadone maintenance therapy (MMT) is the most widely used opioid agonist treatment for opioid dependence in the world. To determine the effectiveness of MMT compared with no treatment or treatments not including agonist treatment in patients with opioid dependence, Cochrane Collaborative researchers conducted a systematic review of clinical controlled trials conducted between 1969 and 2008. Eleven randomized controlled trials including 1969 patients in 5 different countries were identified. Outcome measures included treatment retention, mortality, opiate-positive drug test results, self-reported heroin use, and criminal activity. Study control groups included patients who received a double-blind placebo, those who received methadone for detoxification only, those who received counseling only, those wait-listed for treatment, or those who received no treatment. The mean dose of methadone among patients in the MMT group was 60 mg or higher in most studies.

• Methadone maintenance significantly increased retention in treatment (relative risk [RR], 4.44), decreased morphine-positive drug tests (RR, 0.66), and decreased self-reported heroin use (no pooled effect estimate due to heterogeneity).

• Pooled estimates of mortality risk and criminal activity were reduced (RR=0.48 and 0.39, respectively), but these changes were not statistically significant.

Comments:

There is strong clinical trial evidence that, among opioid-dependent patients, MMT increases treatment retention and reduces heroin use compared with placebo, detoxification, drug-free counseling, and wait-list controls. Other beneficial outcomes from MMT, such as reduced mortality, reduced criminal activity, reduced HIV seroconversion, reduced HIV risk behaviors, and improved birth outcomes, are supported by observational evidence.

Alexander Y. Walley, MD, MSc

Reference:

Mattick RP, Breen C, Kimber J, et al. Methadone maintenance therapy versus no opioid replacement therapy for opioid dependence. Cochrane Database Syst Rev. 2009(3): CD002209.