Sentinel Surveillance of Substance-Related Poisonings in Canada: Spotlight on Opioids Published: ()
Substance-related poisonings and injuries in Canada have received increasing attention in recent years, due to emerging public health threats most notably associated with the opioids overdose crisis, cannabis legalization, and the emergence of electronic cigarettes on the Canadian market.
This data blog presents statistics on poisonings from select substances, and includes a spotlight on opioids. It is the second in a data blog series presenting statistics on substance-related poisonings reported by the Canadian Hospitals Injury Reporting and Prevention Program (CHIRPP). The first data blog presented key findings from recent surveillance studies based on analyses of the electronic CHIRPP database (eCHIRPP).
Subsequent data blogs will present timely eCHIRPP statistics on a variety of substances throughout 2020-2021, and more detailed scientific papers are also planned for 2021 and thereafter. This work helps to shed light on substance-related harms in Canada, and complements information from other data sources.
The surveillance of injuries and poisonings by CHIRPP and other initiatives has continued throughout the COVID-19 pandemic, and future surveillance studies will consider its impacts on the burden of substance-related poisonings and other contexts.
What we know about opioid-related harms and federal action in Canada
Based on work by Canada’s federal, provincial and territorial Special Advisory Committee on the Epidemic of Opioid Overdoses, between January 2016 and March 2020 there were 16,364 apparent opioid-related deaths in Canada.Footnote 1 In 2020 (January to March), 72% of these deaths involved one or more types of non-opioid substances.Footnote 1 Many fatal overdoses result from the illegal drug supply containing highly toxic synthetic opioids like fentanyl and fentanyl analogues.Footnote 2 Between January 2016 and March 2020, 20,523 opioid-related poisoning hospitalizations occurred in Canada (excluding Quebec).Footnote 1 There is little evidence that the crisis is abating. Despite efforts to address the opioid overdose crisis, the ongoing COVID-19 pandemic has resulted in notable increases across Canada.Footnote 3Footnote 4 More information on the actions taken by the Government of Canada to address the opioid overdose crisis can be found under Federal Actions on Opioids-Overview.Footnote 5
What we know about substance-related poisonings from eCHIRPP:
How were the cases identified?The eCHIRPP database was queried on July 13, 2020 to select all cases that were recorded in the database up to and including June 30, 2020 with an injury date of April 1, 2011 onward, and where the first (most severe) diagnosis was a poisoning (n = 36,437 poisonings, equal to 2.8% of eCHIRPP records).
Among those, poisoning cases related to select non-medical drugs and illegal drugs, and/or opioid medications including those containing opioids (e.g. oxycodone, fentanyl, Tylenol® with codeine, cough syrup containing codeine, and others) were selected for this study. Cases were identified using a combination of pre-defined numerical codes and a wide variety of bilingual keywords describing both pharmaceutical and generic names of medications, and technical and familiar names of non-medical and illegal drugs. This included any of the following substances: alcohol, cannabis, methamphetamine, opioids (including codeine, oxycodone, morphine, heroin, fentanyl, and others), cocaine, and e-cigarettes/vaping products.
How many substance-related poisoning cases were there, and what was the distribution of the substances used?
Overall, 40.0% of poisoning cases (14,569 out of 36,437 poisoning cases) involved at least one of the following substances: alcohol, cannabis, methamphetamine, opioids, cocaine, and e-cigarettes/vaping products. This is equal to 1% of all eCHIRPP records during the study period.
Alcohol was most commonly reported, and the ranking of all six substances is as follows:
- Alcohol (n = 10,575, 72.6% of cases)
- Cannabis (n = 2,931, 20.1% of cases)
- Methamphetamine (n = 1,694, 11.6% of cases)
- Opioids (n = 1,656, 11.4% of cases)
- Cocaine (n = 1,011, 6.9% of cases)
- E-cigarette/vaping products (n = 107, 0.7% of cases)
Note that these percentages do not add to 100% because many patients reported using more than one substance at a time (polysubstance use).
Sex and age
Sex and age statistics are presented as proportions of all cases in the eCHIRPP database. This is a more accurate representation of the burden of substance-related poisonings among males vs. females, and age groups, due to the uneven age and sex distribution in the database.
Among females, there were 1,170.4 substance-related poisonings (including involving opioids) per 100,000 eCHIRPP records compared to males at 1,059.0 cases per 100,000 eCHIRPP records.
Regarding opioid-related poisonings (including polysubstance use), among females there were 138.5 cases per 100,000 eCHIRPP records, vs. males at 116.2 cases per 100,000 eCHIRPP records.
Regarding substance-related poisonings among children vs. adults, overall adults aged 20 years and older represented a proportion of 2,815.4 cases per 100,000 eCHIRPP records, compared to children and youth aged 0 to 19 years at 680.9 cases per 100,000 eCHIRPP records.
Adults aged 30 to 39 years represented a proportion of 3,951.7 cases per 100,000 eCHIRPP records, with those aged 40 to 49 years following at 3,749.6 cases per 100,000 eCHIRPP records.
It is important to note, however, that among all substance-related poisonings when considering age and sex together, males aged 40 to 49 years represented a proportion of 4,153.1 per 100,000 eCHIRPP records, followed by females aged 15 to 19 years at 4,011.9 cases per 100,000 eCHIRPP records.
In terms of opioid-related poisonings (including polysubstance use), overall, adults aged 20 years and older represented a proportion of 318.8 cases per 100,000 eCHIRPP records vs. children and youth aged 0 to 19 years at 77.7 cases per 100,000 eCHIRPP records.
Adults aged 30 to 39 years represented a proportion of 551.1 cases per 100,000 eCHIRPP records, with those aged 40 to 49 years following at 419.6 cases per 100,000 eCHIRPP records.
When considering age and sex together among opioid-related poisonings (including polysubstance use), males aged 30 to 39 years represented a proportion of 569.6 cases per 100,000 eCHIRPP records, followed by females aged 30 to 39 years at 521.6 cases per 100,000 eCHIRPP records.
What level of in-hospital treatment was needed?
Hospital admission was required for 8.1% of all substance-related poisoning cases (including those involving opioids), compared to 18.2% of opioid-related poisonings (including polysubstance use).
Where did the substance-related poisonings happen?
Location information was unknown in 44.5% of all substance-related poisoning cases. Among cases where location was known (n = 8,028), the most commonly reported location of substance-related poisonings was at a private residence, either the patient’s own home (42.0%) or someone else’s home (18.6%).
Location information was unknown in 27.8% of opioid-related cases. Among cases where location was known (n = 1,197), nearly three-quarters of opioid-related poisonings occurred at a private residence, either at the patient’s own home (60.2%) or someone else’s home (10.0%).
What proportion of cases were intentional self-harm?
Intentional self-harm including suicide attempt was reported among 22.0% of all substance-related poisoning cases (including those involving opioids), compared to 40.3% of opioid-related poisoning cases (including polysubstance use).
What was the intent of using only opioids, vs. combined with other substances?
These findings are from a more in-depth analysis of intent, based on a 25% random sample (n = 386) of opioid-related poisoning cases, to provide a snapshot of what the data show.
Overall, unintentional poisonings involving opioids (used alone or with other substances) were more common than intentional self-harm, in both the full dataset and this sample.
However, when considering intent alongside opioids use alone vs. in combination with other substances, the top three most common specific circumstances reported were:
- Intentional self-harm including suicide attempt involving poisoning from opioids combined with other substances, at 29.0% of cases.
- Unintentional poisoning from using only opioids at, 18.4% of cases.
- Intentional self-harm including suicide attempt involving poisoning from using only opioids, at 14.4% of cases.
Young children finding substances (or suspected to have found substances) represented 12.2% of opioid poisoning cases. Another 1.8% of unintentional opioid-related poisonings were the result of errors in administering medications among children age 0 to 19 years and adults aged 50+ years.
How common was using more than one substance at a time?
The use of more than one substance at a time (polysubstance use) was reported in 19.9% (n = 2,899) of substance-related poisonings cases. The use of three or more substances was reported in 15.2% of polysubstance use cases. The following top three polysubstance use combinations each involved two substances:
- Alcohol with cannabis, in 37.5% of polysubstance use cases (and in 7.5% of all substance-related poisonings)
- Alcohol with meth, in 12.7% of polysubstance use cases (and in 2.5% of all substance-related poisonings)
- Alcohol with cocaine, in 11.5% of polysubstance use cases (and in 2.3% of all substance-related poisonings)
More about the data source
CHIRPP is an injury and poisoning sentinel surveillance system currently operating in the emergency departments of 11 paediatric and nine general hospitals across Canada.Footnote 6Footnote 7 It collects patients’ accounts of pre-event injury circumstances (“What happened?”), and clinical information is added to the data collection form by hospital staff.Footnote 6Footnote 7 CHIRPP captures a more complete picture of the injury event than hospital administrative or mortality data alone, and also identifies less serious injury cases that do not require hospitalization.Footnote 6
This study does not represent all substance-related poisonings in Canada, because CHIRPP operates at select Canadian hospitals, and because this study focussed only on select substances where a poisoning was the most severe diagnosis (in the event of other injuries besides poisoning having been sustained, or the only diagnosis). Teenagers older than 18 years of age, Aboriginal persons and people who live in rural areas may be under-represented in the eCHIRPP database, as most CHIRPP sites are paediatric hospitals located in major cities. Fatal injuries are also under-represented in the eCHIRPP database because the emergency department data do not capture people who died before they could be taken to hospital or those who died after being admitted via another department. Information is continuously being entered into the eCHIRPP database; therefore, some years do not yet have complete data.