PET imaging of dopamine transporter and drug craving during methadone maintenance treatment and after prolonged abstinence in heroin users.

It has been documented that methadone maintenance treatment is effective in reducing drug craving and relevant risk behaviors in heroin users. However, it is not understood whether methadone maintenance treatment impairs the dopamine transporter in the striatum. To establish whether chronic opiate use might impair brain dopamine neurons in humans, we assessed dopamine transporter (DAT) uptake function in the striatum (caudate and putamen), and analyzed the correlation between DAT in the striatum and heroin craving and subjective anxiety in former heroin users with prolonged abstinence and in patients receiving methadone maintenance treatment. Binding of [(11)C]-2beta-carbomethoxy-3beta-aryltropane ([(11)C] CFT) as a brain dopamine transporter ligand was measured with positron emission tomography (PET) in eleven former heroin users with prolonged abstinence, ten patients receiving methadone maintenance treatment and ten healthy control subjects. Heroin craving and subjective anxiety in prolonged abstinence and methadone maintenance treatment groups were assessed and the correlations between DAT of striatum and heroin craving or subjective anxiety were determined. In comparison with healthy control subjects, methadone maintenance treatment subjects had lower DAT uptake function in the bilateral caudate and putamen and prolonged abstinence subjects showed significantly lower DAT uptake function in the bilateral caudate. Moreover, in comparison to the prolonged abstinence subjects, the methadone maintenance treatment subjects showed significant decreases of DAT uptake in the bilateral putamen. DAT uptake function in bilateral striatum was not associated with heroin craving in prolonged abstinence or in methadone maintenance treatment subjects; however, DAT uptake function in the bilateral caudate was significantly correlated with subjective anxiety in methadone maintenance treatment subjects. Our findings suggest that chronic opioid use induces long-lasting striatum dopamine neuron impairment, and prolonged withdrawal from opioids can benefit the recovery of impaired dopamine neurons in the brain.

The effect of methadone maintenance on illicit opioid use, human immunodeficiency virus and hepatitis C virus infection, health status, employment, and criminal activity among heroin abusers during 6 months of treatment in china.

PURPOSE: : This study was designed to evaluate the effects of methadone maintenance treatment (MMT) on severity of dependence, depression, human immunodeficiency virus (HIV) and hepatitis C virus (HCV) infection, health status, employment, and criminal activity among heroin abusers after 3 and 6 months of treatment, compared with baseline, in China. METHODS: : A total of 102 methadone maintenance treatment (MMT) patients (87 men and 15 women; mean age, 36.1 years; standard deviation = 6.9) without major medical or psychiatric comorbidity participated in the experimental procedure. They were given oral methadone (maximum daily dose 80 mg, minimum daily dose 30 mg). Opioid use was assessed by twice-weekly urinalysis; HIV and HCV status were assessed by standard blood tests. Questionnaires were administered to assess blood-borne-virus risk behavior, severity of dependence, depression, health status, employment, and criminal activity. Changes over time were evaluated by 1-way analysis of variance (ANOVA) followed by post hoc t tests. RESULTS: : Opioid use was reduced from 26.7 days per month at baseline to 0.7 and 0.0 days at 3 and 6 months, respectively. No participant seroconverted to HIV and HCV positivity during the 6 months of MMT. Health status significantly improved, as did severity of dependence, depression, and criminal activity, after 3 and 6 months MMT. CONCLUSIONS: : The results support the broad beneficial effects of MMT in China.