Pharmaco-economics of community maintenance for opiate dependence: a review of evidence and methodology.

This literature review synthesizes and appraises evidence on the pharmaco-economic value of community maintenance for opiate dependence. Included studies enrolled opiate-dependent subjects aged 18 years or over participating in a community maintenance programme. Cost-effectiveness/cost-utility analyses provided some evidence supporting the value of methadone maintenance in combination with psychosocial services and of heroin co-prescription. Evidence on the pharmaco-economic profile of maintenance with buprenorphine as compared with methadone is mixed. Few studies carried out an economic evaluation alongside a randomised controlled trial and studies adopting a modelling approach suffered from problems with the quality and validity of parameter estimates. Studies were also limited in the range of costs and consequences considered. The cost-benefit literature showed positive net benefits from community maintenance programmes. A longer length of stay of subjects in methadone maintenance was associated with greater reductions in criminal activity. However, measurement of benefits was limited to savings from reduced crime rates. Health benefits were rarely considered. Cost-benefit studies based on a before-and-after comparison were not able to consider the impact of treatment on mortality of opiate-dependent subjects. There is a need for better-designed economic evaluations that examine whether treatment benefits exceed costs, in terms of both financial benefits and health gain.