Health-care providers should be cautious in prescribing opioids for pain, says a UBC researcher after finding that patients receiving such treatments for non-cancer pain are eight times more likely than others to start injection drug use.
“At a time when we’re experiencing a catastrophic overdose epidemic related to a toxic illicit drug supply, it’s deeply concerning to know the higher rate at which these patients are transitioning to injection drug use,” says Dr. Roy Purssell, senior author of and a professor at UBC’s department of emergency medicine. He's also a medical lead of the BC Drug and Poison Information Centre at the BC Centre for Disease Control.
“It’s a wake-up call for health-care providers, who need to be increasingly judicious in managing these medications and supporting the people who are using them,” he said in a statement, cautioning more needs to be done to support the needs of people with chronic pain.
The comes as the illicit drug overdose death rates continues its fatal upward climb.
Previous research has looked at people who obtain prescription opioids through non-medical means such as friends, family or drug dealers. This new study, however, is one of the first studies to look at injection drug use among patients who’ve been medically prescribed opioids.
The research team took a dataset of about 1.7 million people in British Columbia and identified patients who received prescription opioid treatments and classified the treatment as chronic (frequent use longer than 90 days), episodic (infrequent use longer than 90 days), or acute (less than 90 days).
From those numbers, they found 15,000 people who have undergone chronic treatments between 2000 and 2015.
Researchers then considered which people initiated injection drug use based on evidence of a problem related to the use of injectable drugs and an injection-related infection.
That analysis found that four per cent of people receiving chronic opioid treatments initiated injection drug use within five years.
“There may be a number of reasons why we’re seeing people transition to injection drug use, such as increasing tolerance, a need to manage uncontrolled pain or the sudden discontinuation of treatment,” Purssell said.
“Every patient’s journey is unique, and this really highlights the importance of shared decision-making that puts the needs and well-being of the patient first,” he said.
Previous research has identified inadequately managed pain and the denial of pain treatments as risk factors for illicit drug use. That has spurred greater calls for shared decision-making between health-care providers and those living with chronic pain. The aim is to balance the benefits and harms of opioid medications.
The researchers emphasized that the findings should not be used to support involuntary tapering or discontinuation of opioid treatments, scenarios that could increase the risk of harms and lead to illicit drug use in some individuals — potentially increasing risk of overdose and death due to the toxic drug supply.
Fatal overdoses
Data released from the BC Coroners Service in December shows 1,782 British Columbians died of an overdose during the first 10 months of 2021. The toxic drug supply remains among the province’s top causes of death.
However, February 2021 Statistics Canada reporting said that despite a widely held view that medical prescribing contributed to the overdose crisis, one study showed that most cohort members did not have a prescription for a pain-relieving opioid when they overdosed, and half did not have a prescription in the five years prior to their overdose.
There were, however, those who did have prescriptions.
Of those, 87.2% were dispensed in the year prior to the overdose and 45.9% of people were dispensed a prescription opioid product.
However, those opioid products were classified as opioid agonist treatment (23.1%) or pain treatment (22.7%).
The proportion of people who did not have a prescribed opioid product dispensed within the year before their overdose was higher among people who experienced a fatal overdose (61%) than among those who did not (53.3%), Statistics Canada said.
