Opioid prescribing among new users for non-cancer pain in USA, Canada, UK and Taiwan: a population-based cohort study

Research output: Contribution to journalArticlepeer-review

  • External authors:
  • Nadyne Girard
  • David Bates
  • David Buckeridge
  • Therese Sheppard
  • Jack Shiansong Li
  • Usman Iqbal
  • Shelly Vik
  • Colin Weaver
  • Judy Seidel
  • Robyn Tamblyn


Background: The opioid epidemic in North America has been driven by an increase in the use and potency of prescription opioids, with ensuing excessive opioid-related deaths. Internationally there are lower rates of opioid-related mortality, possibly because of differences in prescribing and health system policies. Our aim was to compare opioid prescribing rates in patients without cancer, across five centres in four countries. In addition, we evaluated differences in the type, strength and starting dose of medication and whether these characteristics changed over time.
Methods and Findings: We conducted a retrospective multi-centre cohort study of adults who are new users of opioids without prior cancer. Electronic health records and administrative health records from Boston (U.S.), Quebec and Alberta (Canada), UK, and Taiwan were used to identify patients between 2006-2015. Standard dosages in morphine milligram equivalents (MME) were calculated according to The Centers for Disease Control and Prevention. Age and sex standardized opioid prescribing rates were calculated for each jurisdiction. Of the 2,542,890 patients included: 44,690 were from Boston (U.S.), 1,420,136 Alberta, 26,871 Quebec (Canada), 1,012,939 UK and 38,254 Taiwan. The highest standardized opioid prescribing rates in 2014 were observed in Alberta at 66/1,000 persons compared to 52, 51 and 18/1000 in the UK, U.S. and Quebec, respectively. The median MME/day (IQR) at initiation was highest in Boston at 38 (20-45); followed by Quebec, 27 (18-43); Alberta, 23 (9-38); UK, 12 (7-20) and Taiwan, 8 (4-11). Oxycodone was the first prescribed opioid in 65% of patients in the U.S. cohort compared to 14% in Quebec, 4% in Alberta, 0.1% in UK and none in Taiwan. One of the limitations was that data were not available from all centres for the entirety of the 10-year period.
Conclusions: In this study we observed substantial differences in opioid prescribing practices for non-cancer pain between jurisdictions. The preference to start patients on higher MME/day and more potent opioids in North America may be a contributing cause to the opioid epidemic.

Bibliographical metadata

Original languageEnglish
JournalPL o S Medicine
Publication statusAccepted/In press - 28 Sep 2021