Patients in the US and Canada are likely to receive opioids after surgery

To compare international opioid prescribing rates after surgery, researchers analyzed data on four frequently performed procedures: surgery to remove the appendix, surgery to remove the gallbladder, a minimally invasive procedure to treat a torn meniscus cartilage in the knee and a procedure to remove a breast lump.

Within seven days of discharge, about 75 percent of the patients in the United States and Canada filled an opioid prescription, compared to just 11 percent of the patients in Sweden. By the one-month mark, nearly half of U.S patients had received high-dose opioid prescriptions (i.e., prescriptions totaling more than 200 MME) -- nearly double the rate in Canada (25 percent) and nine times higher than the rate in Sweden (5 percent).

"Our findings reveal stark differences in prescribing practices across the three countries and suggest real opportunities to encourage more judicious use of opioids before and after surgery for patients in the United States and Canada," said the study's corresponding author Mark D. Neuman, MD, an associate professor of Anesthesiology and Critical Care and Chair of the Penn Medicine Opioid Task Force. "While innovative strategies, like enhanced recovery protocols, have helped to reduce the number of prescribed opioids, it's clear that we need to continue to identify ways to improve prescribing practices in the United States and Canada."

Opioids, such as codeine, tramadol and morphine, are routinely prescribed for postoperative pain management in many countries. However, recent research suggests that overprescribing opioid medications for short-term pain may be widespread in the United States. The excessive prescribing can increase the risk of drug diversion, new long-term opioid use and the development of opioid use disorder. In the last decade, opioid overdose deaths have significantly increased in countries across the world, including the United States and Canada -- which have the highest opioid use per capita in the world.

While the use of opioids varies in countries worldwide, there has been little research -- until now -- that characterizes the international disparities in opioid use for specific indications, such as pain relief after surgery. In their analysis, researchers examined data from more than 220,000 cases -- ranging from 2013 to 2016 -- to identify differences in the percentage of opioid prescriptions filled within seven and 30 days of the procedures, as well as the quantity and types of opioids dispensed. They specifically sought patients who shared similar characteristics, including age and medical history, and who had not received an opioid in the 90 days prior to the surgery.

Researchers found that at least 65 percent of patients in the United States and Canada filled an opioid prescription in the first seven days after each procedure. In Sweden, the prescribing rate didn't exceed 20 percent for any of the procedures. Meanwhile, the average dosage of the initial prescription in the United States was 247 MME -much higher than the dosage dispensed in Sweden (197) and Canada (169). In addition to the disparities in prescribing rate and dosage, researchers also identified a significant variation in the types of opioid medication prescribed. For example, codeine and tramadol accounted for 58 percent of the postoperative prescriptions dispensed in Canada and 45 percent of the prescriptions in Sweden, but just 7 percent of prescriptions in the United States. In the United States, hydrocodone and oxycodone were the most commonly dispensed opioid medications.

"Our findings point to systematic differences in practitioners' approaches to opioid prescribing, public attitudes regarding the role of opioids in treating pain and broader structural factors related to drug marketing and regulation," said Dr. Karim Ladha, a clinician-scientist at the Li Ka Shing Knowledge Institute of St. Michael's Hospital and co-author of the study.

The work was supported, in part, by a grant from the National Institutes of Health (1-R01-DA042299) and ICES.