Efficacy of maintenance treatment with naltrexone for opioid dependence: a meta-analytical review.
OBJECTIVE
To determine the efficacy of naltrexone in reducing illicit opioid use and the potential moderating role of treatment retention.


METHODS
First, randomized controlled trials (RCTs) comparing the regimens of treatment using the opioid antagonist, naltrexone, with controls were analysed by meta-analysis for treatment effect with regard to a range of outcome criteria. The degree of heterogeneity was also determined. The moderating effect of other interventions during naltrexone maintenance was then estimated, particularly with regard to their effect on treatment retention.


METHODS
Fifteen studies involving 1,071 patients were found.


METHODS
All available outcomes were analysed in 10 studies of naltrexone versus control (seven placebo) and six studies of randomized psychosocial/psychopharmacological interventions.


RESULTS
Significant heterogeneity was found in the efficacy of naltrexone. Level of retention in treatment was found to be a moderator, explaining most of the heterogeneity found. Overall, naltrexone was significantly better than control conditions in reducing the number of opioid-positive urines. This effect was only present in the high retention subgroup for differences in retention. Contingency management (CM) increased retention and naltrexone use, resulting in a reduced number of opioid-positive urines.


CONCLUSIONS
Retention is important to the effect of naltrexone in treating opioid dependence. Contingency management is a promising method of increasing retention.
Department of Clinical Alcohol Research, Malmö University Hospital, Lund University, Malmö, Sweden. bjorn_axel.johansson@med.lu.se
Björn Axel
BA
Johansson
Mats
M
Berglund
Anna
A
Lindgren
D003131:Combined Modality Therapy; D006801:Humans; D009271:Naltrexone / Q000627:therapeutic use*; D009292:Narcotic Antagonists / Q000627:therapeutic use*; D009293:Opioid-Related Disorders / Q000534:rehabilitation*; D011613:Psychotherapy; D016032:Randomized Controlled Trials as Topic
D009292:Narcotic Antagonists; D009271:Naltrexone