Paul Brent, who wrote a cannabis guide for seniors, speaks with manager Autymn Cooke at Dutch Love Cannabis in Scarborough, Ont., on July 21, 2021.Peter Power/The Globe and Mail
The number of older Canadians seeking emergency medical treatment from cannabis poisoning has risen sharply in the years since legalization, new research has found.
A study published in JAMA Internal Medicine on Monday says the number of seniors visiting Ontario emergency departments with cannabis poisoning tripled between 2015 (prelegalization) and 2022 (after edible cannabis became legal and available for retail sale). In the years since 2018, when cannabis first became legal, its use among those over the age of 65 has grown faster than in any other age group.
“Our message is not abstinence. We’re not trying to discourage all seniors from using cannabis,” said Nathan Stall, a geriatrician at Sinai Health and lead author of the study.
“But with legalization, there have been some observed harms. And it’s important that we recognize and address these harms.”
Older adults can face higher risks of adverse effects from cannabis. Because they are more likely to be taking other medications, they’re more likely to suffer from drug interactions, the study says. Declining kidney and liver functions can also mean older adults have a decreased ability to metabolize cannabis.
And, because older adults are already at higher risks of injury or falls (because of loss of balance, vision and strength), cannabis use can further increase that risk.
As a result of these factors, the effects of cannabis poisoning on these populations can be that much more severe, Dr. Stall said.
“When I’ve seen these individuals, they are at a decreased level of consciousness, they’re very confused. Some of them are hallucinating, and require emergency care. Some of them require hospitalization.”
Compared with other age groups, cannabis use among older Canadians is still relatively low (7 per cent compared with 10 per cent of those 45-64, and 25 per cent of those 25-44). But a Statistics Canada report found that older adults are the fastest-growing age group for cannabis consumption, with over 400,000 reporting they had tried it by the end of 2019, compared with just 40,000 in 2012.
The actual numbers of cannabis poisonings among older adults may be much higher, the new study suggests.
“Our study is limited to emergency department visit data and may underestimate the true magnitude of cannabis poisonings,” it says. “Older adults may have sought care elsewhere or not at all, especially since the legalization of edible cannabis immediately preceded the COVID-19 pandemic.”
The latest figures align with similar findings in the U.S., where a 2023 study found that cannabis-related visits to the ER in California increased between 2005 and 2019 by 1,804 per cent.
Seniors use cannabis for a variety of reasons, according to a 2023 Health Canada survey, including for medicinal purposes (such as pain management, for help in managing stress or anxiety or as a sleep aid).
But a significant number of older adults treated for cannabis poisoning were also for accidental ingestion, Dr. Stall said: “I’ve seen this clinically – where an older adult has confused an edible cannabis product for a non-cannabis food.”
A similar study from last year found that hospital visits as a result of unintentional cannabis poisoning among children increased sixfold in Canada following legalization.
“Edible cannabis products are visually attractive. They’re often palatable. They can be taken in error and they’re easily confused with non cannabis foods and candies,” Dr. Stall said.
He said that cannabis products should be treated with the same care as prescription medications or other potentially harmful substances – and preferably, in locked locations.
Another big part of the problem, he added, is the misconception that seniors don’t use cannabis. And as a result, drug education neglects them.
The 2023 Health Canada survey found that almost all of the respondents said they could not recall any public education targeted specifically at older adults.
“Top of mind information or advertisements were generally limited to campaigns targeting a younger age group,” the survey found.
“We need to avoid age-related biases and ageism, in thinking that older adults are not using drugs,” Dr. Stall said. “And that means that patients and health care providers have to have open, judgment-free conversations about cannabis use.”