Quitting drugs like heroin and other opiates is tough, and the withdrawal symptoms, although not fatal, can be very uncomfortable. I have heard some people say that these drugs ‘get in your bones’, and the detox or ‘rattle’ as it is sometimes described is like a heavy dose of the flu.
Opioid dependence is far from a niche problem with an estimated 40 million people globally experiencing this difficulty. So, it is useful to have an opiate substitute to help wean individuals off their dependence on heroin and other similar drugs. This type of treatment is referred to as opioid agonist treatment or ‘OAT’ for short. Two of the most widely prescribed OAT substitutes are methadone and buprenorphine.
A recent systematic review and meta-analysis by Degenhardt and colleagues (2023), published in The Lancet Psychiatry, aimed to answer an important and persistent question:
- Which – if any – of the following medications, buprenorphine and methadone, is effective for the treatment of opioid dependence as assessed by several measures in randomised trials and observational studies?
The authors were thorough in their approach to exploring this question. Searching from the inception of databases like Medline or PsychInfo up to August 2022 they found 83 randomised controlled trials and 193 observational studies. Altogether these studies included just over one million participants, an impressive number of participants given the specialist nature of this treatment.
Prior to reviewing these studies, the authors established primary and secondary outcomes. Three primary outcomes were identified:
- Retention in treatment
- Adherence to treatment
- Additional opioid use over and above the prescribed medication.
All three are important factors when considering the effectiveness of OAT as an intervention. For example, there is evidence that the longer someone stays in treatment the greater their chances of success.
A number of secondary outcomes were proposed and these broadly fell into two groups:
- The first was the use of other drugs like cocaine and cannabis, and
- the second was engagement with the criminal justice system and any criminal activity.
The results were clear, based on the primary outcome of retention in treatment methadone was superior to buprenorphine. It is encouraging to read that this is based on self-reporting i.e., client preference as well as objective measurement.
For secondary outcomes there were no statistically significant differences that could be detected.
This is an important piece of research which has answered a lingering question, namely is one of these OAT drugs (methadone or buprenorphine) superior to the other. Yes, is the answer when it comes to ensuring people stay in treatment. However, staying in treatment isn’t enough. We also need to know how to improve the quality of life for those in treatment and consider any treatment preferences that they might have.
Other important aspects include reducing contact with the criminal justice system, enhancing mental health and reducing use of other drugs. These are just as important as the amount of time spent in treatment given the high rates of co-occurring mental health problems that people dependent on opiates have, and the reality that most people will be using more than one drug.
Strengths and limitations
It is disappointing to read yet again that only half of the primary studies reported on the gender of participants. This is such a basic but critical demographic. It shouldn’t take much effort for authors to collate and report gender. Without this variable how can we discern whether any intervention is effective or not for women? There appears to be a stubborn and persistent attitude among some researchers that gender doesn’t matter and that we can simply transfer any research intelligence gathered from male participants onto females, yet we can’t.
The majority of studies were located in North America and Europe. However, the authors did find some studies from Africa and Asia, two parts of the world that tend to be under-reported. As with gender, we can’t assume that Western-orientated interventions will work in different cultures and regions with significantly differing health and social infrastructure.
Implications for practice
The clear implication for practice from this research is that when it comes to retaining individuals in treatment, methadone has the edge over buprenorphine. However, time alone is not enough. It is just as important to consider client rather than clinician preference as to which they would like.
One of the main reasons for providing OAT in addition to relieving opioid withdrawal symptoms is encouraging behaviour change. Dependence on drugs like opiates is often about routine and habit, whether this be the ritual of preparing the drug for use or how it is sourced, and the social contacts and identity associated with using the drug. Erasing or at least changing these patterns can be as fiendishly difficult as overcoming any physiological dependence on the drug. Years of entrenched behaviour won’t evaporate by introducing a substitute drug. Ensuring there is skilled and timely talking therapy to accompany the pharmacological intervention is absolutely critical.
Statement of interests
No competing interests.
Degenhardt, L., Clark, B., Macpherson, G., Leppan, O., Nielsen, S., Zahra, E., Larance, B., Kimber, J., Martino-Burke, D., Hickman, M. and Farrell, M., 2023. Buprenorphine versus methadone for the treatment of opioid dependence: a systematic review and meta-analysis of randomised and observational studies. The Lancet Psychiatry.