Thunder Bay, Ont., has the seventh-highest rate of hospitalizations due to opioid poisoning in Canada, a new study by the Canadian Institute for Health Information (CIHI) shows.

The new study, released Thursday, measures emergency room admissions and hospitalizations due to opioid poisoning, based on 2016-2017 data.

For hospitalizations, the Thunder Bay census metropolitan area (CMA) had an age-adjusted rate of 27.4 per 100,000 people, meaning about 27 people per 100,000 were hospitalized due to opioid poisoning in 2016-2017.

Thunder Bay's hospitalization rate ranks fourth-highest in Ontario, behind Brantford, London and Peterborough, CIHI said.

CIHI also collected data on emergency room visits due to opioid poisoning but only had complete information for hospitals in Ontario and Alberta. That data shows that, of the areas surveyed, the Thunder Bay CMA again had the seventh-highest rate, with 63.2 per 100,000 people.

That's about double the rate for Ontario and the fifth-highest in the province, behind Brantford, St. Catharines-Niagara, Barrie and Peterborough.

Data comes from Canadian hospitals

The data used comes directly from Canadian hospitals, said Michael Gaucher, CIHI's director of pharmaceuticals and health workforce information services.

"We looked at hospitalizations for all of Canada, and we looked at emergency department visits for Alberta and Ontario, which are the two provinces we have complete data for," he said.

"Those are two important measures with respect to monitoring the opioid crisis as far as harms go, the third one being deaths associated with opioids as well. So those three provide the picture of, at least, the more-severe harms that are occurring."

For this report, CIHI included information for individual census metropolitan areas of 100,000 people or more, in addition to provincial data, Gaucher said.

"We thought it would ... be helpful to try to monitor and address the crisis if we knew more what was happening at local levels," he said.

The CIHI website states opioids "include commonly known types such as fentanyl, oxycodone, morphine, codeine and heroin. Certain opioids are prescribed to treat pain and they can often be obtained illegally. They can also create a feeling of euphoria, are highly addictive and too often are deadly."

The data doesn't indicate whether the opioids responsible for the hospitalizations or emergency room visits are from a prescription, stolen or purchased illegally, Gaucher said.

Opioid poisoning rate growing fast among younger populations

The study also looks at age, with seniors, generally, experiencing a higher rate of opioid-related hospitalization. That is often due to complications from chronic conditions for which they're taking opioids, Gaucher said.

The rate of poisoning among people, 15-24, is the fastest-growing across Canada, he said.

"We're seeing more hospitalizations in younger groups," Gaucher said. "The emergency department visits overall, we're just seeing more of those being younger people."

"What we sense is it's just becoming more of a crisis in general in younger populations."

​Different factors affect rates

There are different factors that play into the number of opioid poisonings in different areas of the country, Gaucher said.

"When you think of the illicit market, just the supply and availability of illicit drugs on the street can differ amongst provinces and amongst cities and even rural areas," he said. "You also have differences in prescribing of opioids; prescribing practices amongst physicians vary."

The overall health of a community is a factor, as are different regulations that may restrict how often opiods are prescribed.

"If there are more intensive harm-reduction strategies that are successful, it may be contributing to some lower rates," Gaucher added.

Useful in public health response to crisis

Gaucher said the new CIHI report will be useful in terms of the public health response to the opioid crisis.

"If they know there's more harms, for example, in these areas, and there's more harms among these groups of people, they can target certain strategies to really hopefully address those situations," he said.

"Longer-term, continuing to monitor this data will just allow us to see how this is progressing."

The full report is available on the CIHI website.