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One in five opioid overdoses involves alcohol: study


Despite a decline in alcohol involvement in opioid-related deaths over past decade, one in five fatal opioid overdoses still involved alcohol in 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).

“While it is well known that patients receiving opioids should refrain from alcohol consumption, we found that 22 per cent of the opioid-related deaths between 1993 and 2013 involved alcohol,” 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.

The 20-year study of all opioid-related deaths in Ontario from 1993 to 2013 showed that the rate of opioid-related deaths increased 288 per cent from 11.9 per million in 1993 to 46.2 per million in 2013. The rate of opioid-related deaths without alcohol involvement increased 388 per cent from 7.4 per million to 36.1 per million, while deaths involving alcohol increased by 125 per cent from 4.5 per million to 10.1 per million.

The researchers identified 6,702 opioid-related deaths between 1993 and 2013, of which 1,496 involved alcohol.

“An important finding of this study was that, while the annual number of opioid-related deaths involving alcohol rose, the proportion of opioid-related deaths involving alcohol declined from 38 per cent in 1993 to 22 per cent by 2013,” adds Gomes.

The researchers add that the study showed a seven-fold increase in accidental opioid-related deaths over the study period. By 2013, nearly two-thirds of all opioid-related deaths in Ontario were accidental and did not involve alcohol.

“The steep increase in opioid-related deaths in Ontario has been driven by accidental deaths and coincided with the introduction of long-acting oxycodone to the public drug formulary in Ontario in 2000.” adds Gomes. This highlights the contribution of prescribed opioids on rising rates of fatal opioid overdoses in Canada, and demonstrates that the majority of these deaths may be avoidable.

The study “Prevalence and characteristics of opioid-related deaths involving alcohol in Ontario, Canada,” was published today in the journal Drug and Alcohol Dependence.

Author block: Tara Gomes, David N. Juurlink, Muhammad M. Mamdani, J. Michael Paterson and Wim van den Brink.

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.


Deborah Creatura
Media Advisor, ICES
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Kelly O’Brien
Communications Advisor – Media 
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