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Background: According to a recent Portuguese study the prevalence of lifetime consumption of heroin in the global population (age range: 15-74 years) is 0.5%. Methadone is the standard pharmacological treatment, while buprenorphine has been available since 1999 as an alternative treatment. Nevertheless, no comparative economic evaluation of the costeffectiveness of these therapies has been made available. Aim: This study estimates the cost-effectiveness and cost-utility of a fixed dose combination of buprenorphine-naloxone (B/N) versus methadone as substitution treatments for opioid drug dependence from the Portuguese social perspective. Material and Methods: The comparator for B/N was methadone treatment, which is the most common pharmacological therapy and current clinical practice in Portugal. Health gains were measured using the number of heroin-free days per year (indicator of effectiveness) and quality-adjusted life years (QALYs) associated with each treatment. Estimated costs included acquisition, preparation and transport of medication; costs of dispensing and supervision of administration; costs arising from the periodic monitoring of patients and the nonmedical direct costs of crime associated with drug addiction. Results: The B/N combination is associated with an incremental cost-utility ratio of €5,914 per QALY gained. The B/N combination is dominant when the analysis includes costs of crime associated with drug addiction. Conclusions: The results suggest that this combination is cost-effective and has the potential to generate health gains in the target population at a low cost.

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... International studies have suggested that methadone ORT may deliver better retention than buprenorphine [15][16][17][18]. However, none was set in a UK treatment setting. ...
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An accumulating body of research suggests that former heroin abusers in methadone maintenance therapy (MMT) exhibit deficits in cognitive function. Whether these deficits are present in former methadone maintained patients following discontinuation of MMT is unknown. This study tests the hypothesis that former heroin users who have detoxified from methadone maintenance therapy and are drug-free have less pronounced cognitive impairment than patients continuing long-term MMT. A series of neuropsychological tests were administered to three groups of subjects: 29 former heroin addicts receiving methadone maintenance treatment, 27 former heroin addicts withdrawn from all opiates, and 29 healthy controls without a history of drug dependence. Testing included Wechsler Adult Intelligence Scale-Revised Vocabulary Test, the Stroop Color-Word Test, the Controlled Oral Word Association Test, the Benton Visual Retention Test, and a Substance Use Inventory. Both methadone-maintained and abstinent subject groups performed worse than controls on tasks that measured verbal function, visual-spatial analysis and memory, and resistance to distractibility. Abstinent subjects performed worse than their methadone maintained counterparts on tests measuring visual memory and construct formation. Cognitive impairment did not correlate with any index of drug use. We confirmed previous findings of neuropsychological impairment in long-term MMT recipients. Both patients receiving MMT and former heroin users in prolonged abstinence exhibited a similar degree of cognitive impairment. Cognitive dysfunction in patients receiving methadone maintenance may not resolve following methadone detoxification.
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Research on the neurocognitive characteristics of heroin addiction is sparse and studies that do exist include polydrug abusers; thus, they are unable to distinguish neurocognitive effects of heroin from those of other drugs. To identify neurocognitive correlates specific to heroin addiction, the present study was conducted in St. Petersburg, Russia where individuals typically abuse and/or become addicted to only one substance, generally alcohol or heroin. Heroin addicts were recruited from an inpatient treatment facility in St. Petersburg. Three comparison groups included alcoholics, addicts who used both alcohol and heroin, and non-abusers. Psychiatric, background, and drug history evaluations were administered after detoxification to screen for exclusion criteria and characterize the sample. Executive Cognitive Functions (ECF) that largely activate areas of the prefrontal cortex and its circuitry measured include complex visual pattern recognition (Paired Associates Learning), working memory (Delayed Matching to Sample), problem solving (Stockings of Cambridge), executive decision making (Cambridge Decision Making Task), cognitive flexibility (Stroop Color-Word Task) and response shifting (Stop Change Task). In many respects, the heroin addicts were similar to alcohol and alcohol+heroin dependent groups in neurocognitive deficits relative to controls. The primary finding was that heroin addicts exhibited significantly more disadvantageous decision making and longer deliberation times while making risky decisions than the other groups. Because the nature and degree of recovery from drug abuse are likely a function of the type or pattern of neurocognitive impairment, differential drug effects must be considered.
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The aim of this study was to compare the mortality associated with oral naltrexone, methadone and buprenorphine in opioid dependence treatment, employing a retrospective data analysis using coronial and prescription data. The number of deaths were identified through national coronial data and number of treatment recipients were estimated from 2000 to 2003 prescriptions and restricted medications data. Mortality rates were expressed as deaths per number of treatment episodes and per person-years at high and low risk of fatal opioid overdose. Thirty-two oral naltrexone, one buprenorphine and 282 methadone-related deaths were identified. Mortality rates in the highest risk period in deaths per 100 person-years were 22.1 (14.6 - 32.2) for oral naltrexone following treatment cessation and 3.0 (2.3 - 3.9) for methadone during treatment induction. Rates in the lowest risk period in deaths per 100 person-years were 1.0 (0.3 - 2.2) during oral naltrexone treatment and 0.34 (0.3 - 0.4) during post-induction methadone treatment. The relative risk of death for oral naltrexone subjects was 7.4 times (high-risk period, p < 0.0001) or 2.8 times (low-risk period, p = 0.055) that of methadone subjects. This is the first comparison of mortality associated with these three pharmacotherapies for opioid dependence. The risk of death related to oral naltrexone appears higher than that related to methadone treatment.
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