[Psychiatric disorders associated with high-dose methadone (>100 mg/d): a retrospective analysis of treated patients].
Recent studies show that high-dose methadone (>100 mg/d) allow a better control of the consumptions of illicit opiates by treated patients. The aim of this retrospective study was to analyze data of patients requiring high-dose methadone (>100 mg/d) as well as associated factors. We retrospectively reviewed charts of treated patients with high-dose methadone followed in the maintenance methadone treatment center between 01/01/07 and 01/07/10. The following variables (medical history, psychiatric comorbidities, associated drugs, and polyaddictions), were assessed with high-dose methadone, using an univariate and then a multavariate analysis. The threshold value of 130 mg/day (median of maximal daily dose) was used to perform analysis. During the study period, 78 patients, mainly men (75.6%), with a median age of 34 years [22-57] were included. The both groups with posology of methadone ≤ 130 mg/d (n=44) versus posology of methadone >130 mg/d (n=34) were close in term of demographic characteristics, consumption of drugs and associated treatments. Plasma methadone concentrations were higher in patients with the daily doses of methadone superior than 130 mg/d (NS), as well as the methadone metabolite (EDDP, p=0.048). Among studied factors, the presence of psychiatric comorbidities was significantly associated with high-dose methadone (threshold 130 mg/d) [OR 4,6 IC 95% (1.412;14.925)]. Seven patients presented with complications related to methadone: cardiac disorder (3), libido troubles (3) and hypofertility (1). Patients requiring high-dose methadone are polydrug addicts. In our study, patients with psychiatric comorbidities needed daily dose of methadone significantly more raised.