Those who terminated their OMT in our study constitute a heterogeneous group, and the reasons for their discharge were varied. Their mortality was high. After the cessation of OMT there was considerable instability with regard to situational status over time, but there were many who returned to periods of maintenance treatment.
Our study showed that 77 % of the discharges from OMT during the observation period were undertaken voluntarily. The introduction of the reform of the care system for substance users in 2004 established a clear distinction. Before 2004, the proportion of involuntary discharges amounted to 44 %, after 2004 this proportion declined to 8 %.
Of the surviving patients who were discharged, nearly half were back in maintenance treatment in June 2011, either in the form of OMT or with another substitution medication administered by a GP. In other words, nearly one-half alternated between being in and outside of OMT.
In our material approximately one in ten of those who had terminated their OMT were considered to be drug-free or in medication-free treatment in June 2011. This indicates that a small number of OMT patients do well without substitution treatment over time. Those who succeed in achieving a drug-free life after OMT are characterised by having ceased to use substances, a desired and planned tapering off of medication and a network consisting of drug-free friends/family members
Untreated opioid-addicted persons have a high mortality rate. International studies have estimated this rate at between 2 % and 4 % per year
(15, 16). In Norway, the mortality rate was found to be 2.4 % per year for those who were on a waiting-list for OMT and a mortality rate of 1.4 % for those who were undergoing treatment (5).
In this study, the mortality rate for those who had terminated their OMT amounted to 4 % per year during the period 2009 – 2011. Most deaths affected the group described as substance users in 2009. Terminated OMT and continued substance use outside of OMT appears to be a combination resulting in a high risk of death. The observed mortality rate is somewhat higher than a previously documented national estimate of mortality after OMT (3.4 % per year), based on data from 1998 – 2003
(5). More than 50 % overdoses as a cause of death following termination of treatment, as observed in this study, concurs with the national estimate (12).
In a Swedish study of 38 patients who had remained under stable methadone treatment for more than ten years, it was found that those who were involuntarily discharged from the treatment had a poorer outcome than those who tapered their medication voluntarily, in terms of substance use and perceived quality of life
(14). Thirteen patients attempted to taper their methadone treatment voluntarily in the course of 15 years. Seven did this successfully and lived a reportedly opiate-free life (14). Most of these had stable family and social conditions when they terminated their OMT. The proportion of drug-free patients in Vest-Agder county was somewhat lower than in the Swedish study, but viewed as a whole, these studies indicate that only a small proportion of those who terminate their OMT succeed in maintaining a drug-free life in the long term.
According to the Swedish study, characteristics of those who succeeded in maintaining a drug-free life without OMT medication include many years of stable OMT, establishment of drug-free networks and a desire to taper their medication
(14). Only one in ten of those who terminated their OMT in Vest-Agder county lived a drug-free life, compared to one in three of those who remained in OMT over the last year. This is in line with a Cochrane summary showing the benefits of OMT compared to no treatment with regard to overcoming addiction problems (17).
A large group failed to report for OMT (n = 28). Of those who died (n = 23), these non-planned and patient-initiated discharges accounted for a full 39 %. Of those who survived, a large proportion were back in OMT or under medication administered by a GP during the observation in mid-2011.
A recent study from Norway shows that crime as an expression of negative behaviour during the treatment increased gradually over the 100 days prior to the termination of the treatment
(18). Hence, it is essential for clinicians to be aware of negative development features, such as increasing substance use and problematic behaviour in the form of crime, and initiate special measures to prevent a premature termination of the treatment sequence. We believe that it is important to establish routines ensuring that new treatment options can be provided at the earliest possible time, thus to reduce the death risk of those who terminate their treatment. Similarly, it will be relevant to assess whether the dosage of OMT medication is adequate or whether a better treatment effect can be achieved by switching to another form of medication (19).
Since OMT is a form of treatment which is based on collaboration between the specialist health services, the social services and the GP, it is essential for all parties to be aware of the risk that may be associated with termination of the treatment and seek jointly to achieve the shared goal: to retain the patient in treatment. In our opinion, it is therefore somewhat disconcerting that nearly one in four GPs do not have a positive view of OMT or have no experience of prescribing OMT medication
(3). Even though the main objective of OMT is retention in treatment and rehabilitation, provisions could also be made for a small group – the long-term stably drug-free patients who have a supportive social framework – to attempt to taper their medication in collaboration with the therapists, if they have the desire to do so.
Strengths and weaknesses of the evaluation
Strengths and weaknesses of the evaluation
This study of a total cohort of OMT patients from the period 1998 – 2009 provides a holistic overview and a systematic summary of treatment results at the department on the basis of all patient records. However, a retrospective review of patient records such as this one will only capture information that the clinicians have become aware of and entered in the hospital’s records. This may cause a bias towards «negative» events that have entailed contact with the hospital, compared to the cases where the patient lives a life without any need for renewed contact with the unit.
The estimates of death, imprisonment and psychiatric treatment will be conservative, since no registry studies or other verification of the information have been undertaken beyond the review of patient records from the OMT department of Vest-Agder county.
Those who terminate their OMT are likely to constitute a group with special challenges related to substance use and co-morbidity when compared to those who remain in the treatment programme over time. In this study we have no specific measures for this possible selection bias.
Patient characteristics and findings from Vest-Agder county largely reflect the national results published in annual status reports and nationwide registry-based studies. The descriptions in our study are therefore deemed to provide a good estimate of reasons for discharge and situational status after OMT in many other regions of Norway.
Lessons for further clinical practice
Lessons for further clinical practice
This study indicates that the group that terminates OMT is predominantly composed of persons who continue to have periods of uncontrolled substance use and a high risk of death.
Even though the majority of those who start OMT stay in this treatment for a long period, a considerable proportion fail to persevere with it. An investigation should therefore be undertaken to reveal possible factors in this treatment option that could help reduce attrition.
A large proportion of those who terminate their OMT later return to make new attempts with OMT or another form of maintenance treatment. Close collaboration with the GPs will therefore be essential for providing follow-up to this group. Provisions should be made to undertake the transitions between different periods or forms of treatment in a unified perspective on patient pathways and continuum of care.
Patients who terminate their OMT should have easy access to readmission without any procedures that may cause unnecessary delay, thus to reduce the risk of complications and death.