Mortality prior to, during and after Opioid Maintenance Treatment (OMG): a national prospective cross-registry study

University of Oslo, Medical Faculty, Institute of Psychiatry, SERAF - National Centre for Addiction Research, Oslo, Norway.
Drug and Alcohol Dependence (Impact Factor: 3.42). 05/2008; 94(1-3):151-7. DOI: 10.1016/j.drugalcdep.2007.11.003
Source: PubMed


Opioid maintenance treatment (OMT) is generally considered to reduce mortality in opiate dependents. However, the level of mortality reduction is still uncertain. This study investigates mortality reductions in an "intention-to-treat" perspective including all dropouts. The mortality reducing effects of OMT are examined both within treatment and post-treatment. The study separates overdose and total mortality reductions.
The study is a prospective cross-registry study with up to 7 years follow-up. All opiate dependents in Norway who applied for OMT (a total of 3789 subjects) were cross-linked with data from the death registry from Statistics Norway. Date and cause of death were crossed with dates for initiation and termination of OMT, and subjects' age and gender. A baseline was established from the waiting list mortality rate. Intention-to-treat was investigated by analysing mortality among the entire population that started OMT.
Mortality in treatment was reduced to RR 0.5 (relative risk) compared with pre-treatment. In the "intention-to-treat" perspective, the mortality risk was reduced to RR 0.6 compared with pre-treatment. The patients who left the treatment programme showed a high-mortality rate, particularly males.
OMT significantly reduces risk of mortality also when examined in an intention-to-treat perspective. Studies that evaluate effects of OMT only in patients retained in treatment tend to overestimate benefits. Levels of overdose mortality will influence the risk reduction. Cross-registry studies as the current one are an important supplement to other observational designs in this field.

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Available from: Helge Waal
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    ABSTRACT: Background The reduction of crime is an important outcome of opioid maintenance treatment (OMT). Criminal intensity and treatment regimes vary among OMT patients, but this is rarely adjusted for in statistical analyses, which tend to focus on cohort incidence rates and rate ratios. The purpose of this work was to estimate the relationship between treatment and criminal convictions among OMT patients, adjusting for individual covariate information and timing of events, fitting time-to-event regression models of increasing complexity. Methods National criminal records were cross linked with treatment data on 3221 patients starting OMT in Norway 1997–2003. In addition to calculating cohort incidence rates, criminal convictions was modelled as a recurrent event dependent variable, and treatment a time-dependent covariate, in Cox proportional hazards, Aalen’s additive hazards, and semi-parametric additive hazards regression models. Both fixed and dynamic covariates were included. Results During OMT, the number of days with criminal convictions for the cohort as a whole was 61% lower than when not in treatment. OMT was associated with reduced number of days with criminal convictions in all time-to-event regression models, but the hazard ratio (95% CI) was strongly attenuated when adjusting for covariates; from 0.40 (0.35, 0.45) in a univariate model to 0.79 (0.72, 0.87) in a fully adjusted model. The hazard was lower for females and decreasing with older age, while increasing with high numbers of criminal convictions prior to application to OMT (all p < 0.001). The strongest predictors were level of criminal activity prior to entering into OMT, and having a recent criminal conviction (both p < 0.001). The effect of several predictors was significantly time-varying with their effects diminishing over time. Conclusions Analyzing complex observational data regarding to fixed factors only overlooks important temporal information, and naïve cohort level incidence rates might result in biased estimates of the effect of interventions. Applying time-to-event regression models, properly adjusting for individual covariate information and timing of various events, allows for more precise and reliable effect estimates, as well as painting a more nuanced picture that can aid health care professionals and policy makers.
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    • "Practices of the courts also fly in the face of the recommendations of United Nations expert bodies on health and drugs as well as highly regarded expert reviews of the Cochrane Collaboration that have investigated both methadone and buprenorphine maintenance with respect to effectiveness and safety [4,36,37]. Numerous studies have shown that MMT keeps people with opioid dependence in treatment longer than the abstinence-based therapies apparently favored by some drug courts, and dropping out of treatment is a major risk factor for overdose [38,39]. "
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    ABSTRACT: Specialized drug treatment courts are a central part of drug-related policy and programs in the United States and increasingly outside the U.S. While in theory they offer treatment as a humane and pragmatic alternative to arrest and incarceration for certain categories of drug offenses, they may exclude some forms of treatment-notably methadone maintenance treatment (MMT). We sought to understand from the perspective of treatment providers whether this exclusion existed and was of public health importance in New York State as a case example of a state heavily committed to drug courts and with varying court-level policies on MMT. Drug courts have been extensively evaluated but not with respect to exclusion of MMT and not from the perspective of treatment providers. Qualitative structured interviews of 15 providers of MMT and 4 NGO advocates in counties with diverse court policies on MMT, with content analysis. Courts in some counties require MMT patients to "taper off" methadone in an arbitrary period or require that methadone be a "bridge to abstinence." Treatment providers repeatedly noted that methadone treatment is stigmatized and poorly understood by some drug court personnel. Some MMT providers feared court practices were fueling non-medical use of prescription opiates. Drug court practices in some jurisdictions are a barrier to access to MMT and may constitute discrimination against persons in need of MMT. These practices should be changed, and drug courts should give high priority to ensuring that treatment decisions are made by or in close consultation with qualified health professionals.
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    • "In treating heroin-dependent persons, opioid maintenance treatment (OMT) combined with psychosocial support has been found to be effective [1,2], and has been linked to improvements in a number of outcomes, including heroin use [3,4], mortality [5-8] and criminal activity [9-15]. OMT is often considered a long-term treatment. "
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    ABSTRACT: Opioid maintenance treatment (OMT) is associated with reduced crime among heroin users, but little is known about how crime changes during different phases of treatment. The aim of this study was to investigate changes in criminal convictions on a day-to-day basis before and after entry or discharge from OMT. National cohort study of all patients (n = 3221) in OMT in Norway 1997-2003. Patients were followed over a 9-year period, before, during, and after treatment. Criminal convictions were studied on a day-to-day basis in relation to treatment status. A time-continuous estimate of the probability of convictions within the population for all days during observation was calculated. Changes in convictions were evident before changes of treatment status. During the 3 years prior to OMT, the convictions rate was approximately 0.4% per day. Prior to OMT, convictions decreased to about 0.2% per day on the day of treatment initiation. During the weeks before dropping out of treatment, convictions increased. The patterns during periods of transition were the same across gender, age and pre-treatment conviction-levels. Changes in convictions often occurred prior to changes in treatment status. Reductions in criminal convictions were found in the period before entry (or re-entry) to OMT, and increases in criminal activity were found in the months prior to treatment interruption.
    Full-text · Article · Oct 2013 · BMC Psychiatry
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