Valutazione dell'efficacia dei trattamenti metadonici a lungo termine effettuati nei Ser.T. della provincia autonoma di Trento

Objectives: The aim of this study is to evaluate "the outcome" of methadonic treatments (long term methadone) given to "heroin-addicts" taken in charge by Drug Addiction Services of the Local Health Unit of the Province of Trento. It focuses specifically on the role played by the methadone dose in determining the success of therapy related to the motivation of the patient to overcoming the situation of drug addiction. Design: retrospective cohort study conducted from 2000 to 2008. Setting: outpatients treatment in Trento Province, Italy. Participants: 1.771 heroine addicts in outpatients treatment in long term methadone therapy (>=180 days) Interventions: patients were categorized into 3 groups on the basis of their clinical characteristics and motivation to change. The group A1(n=679) and A2 (n=327) in high evolution, the group B (n=765) in low evolution. Measurements: for the Group A1 the methadone treatment is aimed at drug free condition; the outcome is the opioid abstinence (negative urine results in 90%-100%); for the Group A2 the methadone treatment is aimed at the "coupling" and symptom stabilization to prepare a future voluntary change for drug free situation; the outcome is the opioid abstinence (negative urine results at least 50%). For the Group B the methadone treatment is aimed at symptom stabilization not oriented to voluntary change of addiction situation; the outcome is the global improving of quality of life (such as reduction of incarceration, of overdose risk, improvement of working days). Methods: The probabililty of successful treatment was estimated by means of multivariate logistic model. The Odds Ratios and 95% confidence intervals were calculated. Results: For the Group A1, there is no statistically significant effect of methadone dose on the probability of successful treatment. For groups A2 and B, to take a methadone treatment higher than 50mg/die determines a higher probability of success (OR = 2.29 Group A2 and OR = 1.83 Group B). Conclusions: Many factors can influence the effects of methadone, therefore, the concept of a specific "range" dose, which may be applied to all patients is scientifically not plausible; it is for this reason that the present study is intended to promote the importance of initial evaluation of the patients in order to build a "custom planned methadone treatment".