There are many stigmas about addiction that are prevalent in society but the underlying cause of them all is that addiction is moral failing, even though we know addiction is a biological disease of the brain (with behavioral symptoms). In addition to being scientifically unfounded, stigmas about addiction can actually affect policy and public health decisions that have a real impact on people’s lives. In the perfect world, every decision we made would be based on concrete evidence and controlled, experimental studies. Unfortunately, this seems to be the exact opposite case for our attitudes as a society and our public policy towards drugs—ignorance, assumptions, and misconceptions seem to dominate. Nevertheless, as scientists, all we can do is the best work we can, explain and communicate the science to as many people as possible, and help to promote and support the work of others. Which brings me to today’s paper: a small pilot study that may have a wide impact on the treatment of addicts in the criminal justice system.
The paper, released in the journal Addiction, looks at how treatment for opioid addiction while in prison can affect the rate of relapse to opioid abuse once inmates are released. The study recruited opioid-dependent male inmates incarcerated in New York City jails that were not interested in maintenance therapy (methadone or buprenorphine). The treatment tested is a new medication, an extended-release naltrexone (XR-NTX), a compound that blocks opioid receptors.
Note on pharmacology: naltrexone is what’s known as a mu opioid receptor (MOPR) antagonist, meaning it blocks activity at MOPR (the molecular target of opioid drugs). It also has a weaker antagonist effect on kappa opioid receptors (KOPR). The KOPR plays a more complicated role in addiction, but several studies have suggested blockade of KOPR may reduce relapse. Extended release means that these receptors remain blocked for a sustained period of time after receiving the initial dose.
While 152 inmates were initially interviewed, only 34 fit the criteria for the study. Many subjects were excluded from the study for a variety of reasons that would have made the study difficult to perform or the data difficult to interpret. For example, no interest, currently on methadone or buprenorphine, tested positive for opioid prior to treatment, and other reasons.
The 34 subjects were randomly assigned to either the group that would receive the XR-NTX or standard behavioral therapy (i.e. no medication given to the patient). 15 (2 of the 17 refused) patients received a single injection of XR-NTX prior to release (average of 5 days before release) and 17 received no medication. Patients that received the XR-NTX were offered a second injection 4-weeks post release and 12 accepted this second injection.
6 of the 16 (1 remained incarcerated so was excluded) that received the first dose of XR-NTX had relapsed to opioid use at 1-4 weeks post-release while 15 of 17 relapsed for the control group. Urine analysis confirmed whether or a not a subject was on opioids.
Granted that these are very small numbers (the authors described the study as a proof-of-principle pilot study) but the data are statistically significant. This means that the effect the experimenters are observing is most likely real and not due to random chance. The results suggest that inmates that receive the XR-NTX medication are less likely to relapse after being released from prison.
These results are important because one of the problems of the US criminal justice system is that addicts are not treated while in prison. While they are abstinent while incarcerated, the underlying neurobiology of their addiction is not being treated which results in almost immediate relapse following release from prison. This of course can result in being thrown back into jail 1) if arrested while using the drug or 2) due to criminal activity to support the addiction. This cycle of addiction-arrest-incarceration-relapse-arrest-incarceration is harmful for the criminal justice system, for the addicts themselves, and for society at large (after all, we are paying for it). This study suggests addicts in prisons that are treated with medication are less likely to relapse.
However, this study is extremely limited and needs to be expanded to a much larger group of inmates before any type of changes can be implemented on a large scale. Furthermore, once released, subjects need to be monitored more closely and for a longer period of time to determine if relapse rate remains low. Other medications prior to release, besides XR-NTX, should also be considered in future analyses.
Most importantly, this study is an example of how treating addiction as a medical disease that requires medical treatments can actually help addicts to stay off of drugs, and hopefully, out of prison.