- B.C. researchers studied opioid agonist therapy during incarceration and non-fatal overdose after release
- OAT medications like methadone or buprenorphine help to manage opioid withdrawal symptoms
- Those who received OAT had a 45% lower risk of non-fatal overdose in the month after release
Evidence suggests that the rate of non-fatal overdose is at least 15 times the rate of fatal overdose, and non-fatal overdose is a risk factor for later fatal overdose and other significant harms.1 Opioid agonist therapy (OAT) involves prescribing medications that reduce opioid withdrawal symptoms and cravings. OAT is an effective approach for treating opioid use disorder and has also been associated with numerous other health benefits, including a reduced risk of overdose.
However, incarceration often disrupts individuals’ access to OAT, both when they enter custody and following their release. This disruption is concerning because the risk of fatal overdose is very high following release from custody. While the relationship between release from custody and the risk of fatal overdose is documented, the relationship between release and the risk of non-fatal overdose is less clear. A study from British Columbia aimed to understand the relationship between receipt of OAT while incarcerated and the risk of non-fatal overdose among people with opioid use disorder in the month after release from custody.2
Study details
The study sample came from the BC Provincial Overdose Cohort (BC-ODC), which is a linked dataset from multiple data sources including healthcare and the legal system. One of the components of the BC-ODC is data from a 20% random sample of individuals in B.C. The study analyzed data for all people within this sample who met the following criteria: they were released from provincial correctional facilities in B.C. between January 1, 2015 and December 1, 2018, they were aged 18 or older at the time of release and they had been diagnosed with an opioid use disorder. The relationships between receiving OAT during incarceration, experiencing non-fatal overdose in the 30 days after release and sociodemographic data were examined.
Study results
A total of 1,535 people were included in the study sample. There were 4,738 incarceration episodes with a median of two custody releases per person. OAT was provided in 56% of incarceration episodes, with buprenorphine/naloxone being the most common medication (it constituted 56% of the OAT dispensed). During the study period, 453 non-fatal overdoses were recorded in the 30 days after release. Twenty-five people died during the study period; 22 of the deaths were from fatal overdoses.
The study found that receiving OAT while incarcerated had a protective effect against the risk of non-fatal overdose after release. After adjusting for several sociodemographic factors, the authors found that individuals who received OAT while incarcerated had a 45% lower risk of non-fatal overdose in the month after release than those who did not receive OAT while incarcerated.
Among the people who received OAT while incarcerated, some had started it in the community before they were incarcerated and others started receiving it during their incarceration. The reduced risk of non-fatal overdose after release was similar for both of these subgroups. Specifically, people who were already on OAT before incarceration and continued it while incarcerated had a 51% lower risk of non-fatal overdose than those who were not on OAT. People who started OAT while incarcerated had a 42% lower risk than those who were not on OAT.
People who received OAT during incarceration were more likely to have been incarcerated for longer, have no chronic conditions, not have a mental health diagnosis and have a history of OAT use.
Differences between men and women
A similar proportion of men (56%) and women (53%) were provided with OAT during incarceration.
Adjusted analyses compared the risk of non-fatal overdose among men and women who received OAT while incarcerated with the risk among those who did not receive OAT. The effect of receiving OAT while incarcerated appears to be larger for women than for men:
- For women, after adjusting for sociodemographic factors, the risk of non-fatal overdose was reduced by 71%.
- For men, after adjusting for sociodemographic factors, the risk of non-fatal overdose was reduced by 40%.
Access to OAT in Canadian prisons
Access to OAT in custody varies between jurisdictions across Canada. This means it can be different depending on whether an individual is incarcerated in a federal facility or in a provincial or territorial facility. In some jurisdictions in Canada, accessing OAT in custody is only possible for people who have a prescription from a community provider when they enter. There can be a number of policy and individual factors that affect people’s ability to start OAT while in custody. These can include an individual patient’s knowledge and preferences, resources and linkages to community-based prescribers, and support from institutional policies and staff.3
Need to improve access to OAT for people who are incarcerated and on release
This study suggests that improving access to OAT for people who are incarcerated will reduce the risk of non-fatal overdose in the 30 days after release, particularly for women.
For service providers who work with individuals while they are incarcerated or after their release, this study highlights the importance of ensuring seamless transitions between custody- and community-based services. Strengthening partnerships between correctional institutions and community health services can help bridge gaps in care, facilitate access to OAT and reduce the risk of non-fatal overdose.
Limitations
This study could only include overdoses where healthcare professionals were involved. This means that there were probably more non-fatal overdoses in the study population than reported. Furthermore, owing to limitations in the administrative data, the authors could not determine whether people had received OAT in the days before their release and they did not examine whether people’s OAT prescriptions continued after their release. There were no data available on race, ethnicity or Indigenous identity, meaning that the researchers could not include this information in their analysis.
REFERENCES:
- Casillas SM, Pickens CM, Tanz LJ et al. Estimating the ratio of fatal to non-fatal overdoses involving all drugs, all opioids, synthetic opioids, heroin or stimulants, USA, 2010-2020. Injury Prevention. 2024 Jan 30;30(2):114-24.
- McLeod KE, Buxton JA, Karim ME et al. Receipt of opioid agonist treatment in provincial correctional facilities in British Columbia is associated with a reduced hazard of nonfatal overdose in the month following release. PloS One. 2024 Jul 1;19(7):e0306075.
- Kouyoumdjian FG, Patel A, To MJ et al. Physician prescribing of opioid agonist treatments in provincial correctional facilities in Ontario, Canada: a survey. PLoS One. 2018 Feb 15;13(2):e0192431.