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One-third of opioid-related deaths in Ontario were among people actively treated with a prescription opioid in 2016


One-third of opioid-related deaths in Ontario were among people actively being treated with prescription opioids in 2016. However, this proportion has decreased significantly since 2013, according to a new study by researchers at the Institute for Clinical Evaluative Sciences (ICES), St. Michael's Hospital and the Ontario Drug Policy Research Network (ODPRN).

This study highlights the important role of prescribed, diverted and illicit opioids in fatal overdoses across the province. Although, in 2016, the majority of opioid-related deaths occurred among people not currently being prescribed these medications from a physician, prescription opioids continue to contribute to opioid-related deaths. For example, among people not actively being prescribed opioids at their time of death, oxycodone, hydromorphone, methadone and morphine were frequently involved in the overdose, implying that these deaths likely involved diverted prescription opioids,” says Tara Gomes, a scientist at ICES and the Li Ka Shing Knowledge Institute of St. Michael’s Hospital and a principal investigator of ODPRN.

Although the role of prescription opioids in opioid-related deaths has decreased since 2013, prescribed, diverted and illicit opioids all played an important role in in opioid-related deaths in 2016. Of the 2,833 opioid-related deaths identified, an active opioid prescription on the date of death was relatively common, but declined slightly throughout the study period (38.2 per cent in 2013 vs. 32.5 per cent in 2016).

“We found a concerning trend of increased non-prescribed fentanyl involvement in 2016, which aligns with the recent introduction of illicit fentanyl to the market. Nearly half of opioid-related deaths among people with no active prescriptions involved fentanyl in 2016, and it is anticipated that this has continued to rise in more recent years,” says Gomes.

Older individuals and women were relatively more likely to have an active opioid prescription at time of death. In 2016, 46.4 per cent of those aged 45 to 64 had an active opioid prescription compared with only 11.6 per cent among those aged 24 or younger. Similarly, 45.6 per cent of women had an active opioid prescription at time of death compared to 26.4 per cent of men.

“It is important to be aware of the complex opioid environment that currently exists in Ontario, where illicit opioids, as well as prescription opioids that are either prescribed or diverted, are playing an important role in opioid-related deaths. Approaches designed to address this issue must consider all of these factors, as well as the inter-relationship between the prescribed and illicit market. For example clinicians who rapidly taper opioid doses in their patients can force a transition to sourcing opioids from illicit sources, which is inherently less safe,” says Gomes.

The study “Contributions of prescribed and non-prescribed opioids to opioid-related deaths: a population-based cohort study in Ontario, Canada,” was published today in the BMJ.

Author block: Tara Gomes, Wayne Khuu, Diana Martins, Mina Tadrous, Muhammad M. Mamdani, J. Michael Paterson and David N. Juurlink.

The Institute for Clinical Evaluative Sciences (ICES) is an independent, non-profit organization that uses population-based health information to produce knowledge on a broad range of healthcare issues. Our unbiased evidence provides measures of health system performance, a clearer understanding of the shifting healthcare needs of Ontarians, and a stimulus for discussion of practical solutions to optimize scarce resources. ICES knowledge is highly regarded in Canada and abroad, and is widely used by government, hospitals, planners, and practitioners to make decisions about care delivery and to develop policy. For the latest ICES news, follow us on Twitter: @ICESOntario

St. Michael’s Hospital provides compassionate care to all who enter its doors. The hospital also provides outstanding medical education to future healthcare professionals in 29 academic disciplines. Critical care and trauma, heart disease, neurosurgery, diabetes, cancer care, care of the homeless and global health are among the hospital’s recognized areas of expertise. Through the Keenan Research Centre and the Li Ka Shing International Healthcare Education Centre, which make up the Li Ka Shing Knowledge Institute, research and education at St. Michael's Hospital are recognized and make an impact around the world. Founded in 1892, the hospital is fully affiliated with the University of Toronto.

St. Michael's Hospital with Providence Healthcare and St. Joseph's Health Centre now operate under one corporate entity as of August 1, 2017. United, the three organizations serve patients, residents and clients across the full spectrum of care, spanning primary care, secondary community care, tertiary and quaternary care services to post-acute through rehabilitation, palliative care and long-term care, while investing in world-class research and education.


Deborah Creatura
Media Advisor, ICES
[email protected]
(o) 416-480-4780 or (c) 647-406-5996

Ana Gajic
Senior Communications Advisor, St. Michael’s Hospital
[email protected]


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