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Immigrants at lower risk of overdose or death following codeine prescription than their Canadian-born counterparts, new study finds


Immigrants are at a lower short-term risk of an overdose or death following codeine prescription, compared to non-immigrants. Even immigrants not proficient in English or French at the time of migration are at lower relative risk of overdose or death following a codeine prescription, new research has found.

“Avoiding medication-related errors including drug overdoses is an ongoing international priority. We anticipated that poor language skills might put some immigrants at a higher risk of adverse drug reactions, but our study shows this just wasn’t the case,” said lead author Dr. Joel Ray, a researcher at both the Institute for Clinical Evaluative Sciences (ICES) and St. Michael’s Hospital.

Codeine is an opioid pain medication that is often used to treat mild to moderately severe pain.

Susceptibility to adverse drug events also has a biological basis, arising from differences in the way the body metabolizes drugs like codeine. Several reports have suggested an increased risk of severe reactions or fatalities after members of certain ethnic groups started codeine, especially those from Eastern African countries like Ethiopia.

Dr. Ray, also a physician at St. Michael’s Hospital, looked at data from ICES on all Ontario residents given a codeine prescription between 2002 to 2012.

In a paper published today in the Journal of Epidemiology and Community Health, he identified 553,504 people newly prescribed codeine and 673,740 people newly prescribed a non-opioid NSAID. Overall, 50,247 of codeine recipients (9.1 per cent) were immigrants or were born to an immigrant mother.

The 30-day rate of overdose or death was 57.1 per 100,000 person-days among Canadian-born patients prescribed codeine, yet that rate was significantly lower among most immigrant groups. Dr. Ray said this may be due to the “healthy immigrant effect,” where immigrants are generally healthier than people born in Canada. Certainly, it did not support the idea that people originating from Eastern Africa are a higher risk of lethal codeine overdose.

Dr. Ray noted that while immigrants in the study were not at higher risk of overdose or death following codeine prescription, it is surprising that those without proficiency in spoken English or French were also at lower risk. Dr. Ray added that more research is needed about the value of medication instructions among specific immigrants or groups who speak or read another primary language.

The study “Risk of overdose and death following codeine prescription among immigrants,” was published today in the Journal of Epidemiology and Community Health.

Authors: Joel G. Ray, Simon Hollands, Tara Gomes, Marcelo Urquia, Erin M. Macdonald, Ping Li, Muhammad M. Mamdani and David Juurlink.

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 more than 23 academic disciplines. Critical care and trauma, heart disease, neurosurgery, diabetes, cancer care, and care of the homeless are among the hospital’s recognized areas of expertise. Through the Keenan Research Centre and the Li Ka Shing International Healthcare Education Center, 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.


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Read the Journal Article